Multispecific Antibody Targeting and Multivalency Through Modular Recognition Domains

ABSTRACT

Antibodies containing one or more modular recognition domains (MRDs) that can be used to target the antibodies to specific sites are described. The use of antibodies containing one or more modular recognition domains to treat disease, and methods of making antibodies containing one or more modular recognition domains are also described.

REFERENCE TO RELATED APPLICATION

The present application is a continuation of and claims the benefit ofpriority to U.S. patent application Ser. No. 13/135,754, filed Jul. 14,2011 (now pending), which claims the benefit of priority to U.S.Provisional Application Ser. No. 61/364,766, filed Jul. 15, 2010 (nowabandoned). U.S. patent application Ser. No. 13/135,754 is also acontinuation-in-part of and claims the benefit of priority to U.S.patent application Ser. No. 12/747,883, filed Jun. 11, 2010 (nowabandoned), which is a national stage application of InternationalApplication No. PCT/US2008/088337, filed Dec. 24, 2008 (now abandoned),which claims the benefit of priority to U.S. Provisional Application61/018,816, filed Jan. 3, 2008 (now abandoned), and U.S. ProvisionalApplication 61/022,767, filed Jan. 22, 2008 (now abandoned). Thedisclosures of the aforementioned patent applications are hereinincorporated by reference in their entirety and for all purposes.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to antibodies containing one or moremodular recognition domains, and more specifically to the use ofantibodies containing one or more modular recognition domains to treatdisease, as well as methods of making antibodies containing one or moremodular recognition domains.

2. Background

Monoclonal antibodies (Abs) with catalytic activity can be used forselective prodrug activation and chemical transformations. Specifically,monoclonal Abs with aldolase activity have emerged as highly efficientcatalysts for a number of chemical transformations, particularly aldoland retro-aldol reactions. The retro-aldolase activity of Abs, such as38C2 and 93F3, have allowed researchers to design, synthesize, andevaluate prodrugs of various chemotherapeutic agents that can beactivated by retro-aldol reactions. (Construction of 38C2 was describedin WO 97/21803, which is herein incorporated by reference). 38C2contains an antibody combining site that catalyzes the aldol additionreaction between an aliphatic donor and an aldehyde acceptor. In asyngeneic mouse model of neuroblastoma, systemic administration of anetoposide prodrug and intra-tumor injection of 38C2 inhibited tumorgrowth.

One drawback in the use of catalytic Abs is that they lack a device totarget the catalytic Ab to the malignant cells. Previous studiesdemonstrated that in an antibody-directed enzyme prodrug therapy (ADEPT)or antibody-directed abzyme prodrug therapy (ADAPT) approach, enzymes orcatalytic antibodies can be directed to tumor cells by chemicalconjugation or recombinant fusion to targeting antibodies.

The development of bispecific or multi-specific molecules that targettwo or more cancer targets simultaneously and/or activate prodrugsoffers a novel and promising solution to attacking cancer and otherdiseases. Such molecules can be based on immunoglobulin-like domains orsubdomains as exemplified in FIG. 1 of the present application. Studiesof bispecific antibodies that simultaneously target two tumor-associatedantigens (e.g., growth factor receptors) for down-regulation of multiplecell proliferation/survival pathways have provided support for thisapproach. Traditionally, bispecific antibodies have been prepared bychemically linking two different monoclonal antibodies or by fusing twohybridoma cell lines to produce a hybrid-hybridoma. Other technologiesthat have created multispecific, and/or multi-valent molecules includedAbs, diabodies, T and Abs, nanobodies, BiTEs, SMIPs, darpins, DNLs,Affibodies, Duocalins, Adnectins, Fynomers Kunitz Domains Albu-dabs,DARTs, DVD-IG, Covx-bodies, peptibodies, scFv-Igs, SVD-Igs, dAb-Igs,Knob-in-Holes, and triomAbs. Although each of these molecules may bindone or more targets, they each present challenges with respect toretention of typical Ig function (e.g., half-life, effector function),production (e.g., yield, purity), valency, and simultaneous targetrecognition.

Some of the smaller, Ig subdomain- and non-Ig-domain-basedmulti-specific molecules may possess some advantages over thefull-length or larger IgG-like molecules for certain clinicalapplications, such as for tumor radio-imaging and targeting, because ofbetter tissue penetration and faster clearance from the circulation. Onthe other hand, IgG-like molecules may prove to be preferred oversmaller fragments for other in vivo applications, specifically foroncology indications, by providing the Fc domain that confers long serumhalf-life and supports secondary immune function, such asantibody-dependent cellular cytotoxicity and complement-mediatedcytotoxicity. Unlike their fragment counterparts, engineering andproduction of recombinant IgG-like multi-specific, multi-valentmolecules has been, however, rather technically challenging due to theirlarge size (150-200 kDa) and structural complexity. Success in thefield, as judged by successful application in animal models, has beenvery limited. Recently, with the examination of a variety of constructs,the efficient expression of Fc domain-containing bi-specific moleculesin mammalian cells has made some strides.

Another approach that has been used to target antibodies is through theuse of peptibodies. Peptibodies are essentially peptide fusions withantibody Fc regions. Given the success of studies using random peptidelibraries to find high-affinity peptide ligands for a wide variety oftargets, fusion of such peptides to antibody Fc regions provides a meansof making peptides into therapeutic candidates by increasing theircirculatory half-life and activity through increased valency.

Protein interactions with other molecules are basic to biochemistry.Protein interactions include receptor-ligand interactions,antibody-antigen interactions, cell-cell contact and pathogeninteractions with target tissues. Protein interactions can involvecontact with other proteins, with carbohydrates, oligosaccharides,lipids, metal ions and like materials. The basic unit of proteininteraction is the region of the protein involved in contact andrecognition, and is referred to as the binding site or target site. Suchunits may be linear sequence(s) of amino acids or discontinuous aminoacids that collectively form the binding site or target site.

Peptides derived from phage display libraries typically retain theirbinding characteristics when linked to other molecules. Specificpeptides of this type can be treated as modular specificity blocks ormolecular recognition domains (MRDs) that can, independently, or incombination with other protein scaffolds, create a single protein withbinding specificities for several defined targets.

An example of such a defined target site is integrin. Integrins are afamily of transmembrane cell adhesion receptors that are composed of αand β subunits and mediate cell attachment to proteins within theextracellular matrix. At present, eighteen α and eight β subunits areknown; these form 24 different αβ heterodimers with differentspecificities for various extracellular matrix (ECM) cell-adhesiveproteins. Ligands for various integrins include fibronectin, collagen,laminin, von Willebrand factor, osteopontin, thrombospondin, andvitronectin, which are all components of the ECM. Certain integrins canalso bind to soluble ligands such as fibrinogen or to other adhesionmolecules on adjacent cells. Integrins are known to exist in distinctactivation states that exhibit different affinities for ligand.Recognition of soluble ligands by integrins strictly depends on specificchanges in receptor conformation. This provides a molecular switch thatcontrols the ability of cells to aggregate in an integrin dependentmanner and to arrest under the dynamic flow conditions of thevasculature. This mechanism is well established for leukocytes andplatelets that circulate within the blood stream in a resting statewhile expressing non-activated integrins. Upon stimulation throughproinflammatory or prothrombotic agonists, these cell types promptlyrespond with a number of molecular changes including the switch of keyintegrins, β2 integrins for leukocytes and αvβ3 for platelets, from“resting” to “activated” conformations. This enables these cell types toarrest within the vasculature, promoting cell cohesion and leading tothrombus formation.

It has been demonstrated that a metastatic subset of human breast cancercells expresses integrin αvβ3 in a constitutively activated form. Thisaberrant expression of αvβ3 plays a role in metastasis of breast canceras well as prostate cancer, melanoma, and neuroblastic tumors. Theactivated receptor strongly promotes cancer cell migration and enablesthe cells to arrest under blood flow conditions. In this way, activationof αvβ3 endows metastatic cells with key properties likely to becritical for successful dissemination and colonization of target organs.Tumor cells that have successfully entered a target organ may furtherutilize αvβ3 to thrive in the new environment, as αvβ3 matrixinteractions can promote cell survival and proliferation. For example,αvβ3 binding to osteopontin promotes malignancy and elevated levels ofosteopontin correlate with a poor prognosis in breast cancer.

For these reasons, and for its established role in angiogenesis, theαvβ3 integrin is one of the most widely studied integrins. Antagonistsof this molecule have significant potential for use in targeted drugdelivery. One approach that has been used to target αvβ3 integrin usesthe high binding specificity to αvβ3 of peptides containing theArg-Gly-Asp (RGD) sequence. This tripeptide, naturally present inextracellular matrix proteins, is the primary binding site of the αvβ3integrin. However, RGD based reporter probes are problematic due to fastblood clearance, high kidney and liver uptake, and fast tumor washout.Chemical modification of cyclized RGD peptides has been shown toincrease their stability and valency. These modified peptides are thencoupled to radio-isotopes and used either for tumor imaging or toinhibit tumor growth.

Integrin αvβ3 is one of the most well characterized integrinheterodimers and is one of several heterodimers that have beenimplicated in tumor-induced angiogenesis. While sparingly expressed inmature blood vessels, αvβ3 is significantly up-regulated duringangiogenesis in vivo. The expression of αvβ3 correlates withaggressiveness of disease in breast and cervical cancer as well as inmalignant melanoma. Recent studies suggest that αvβ3 may be useful as adiagnostic or prognostic indicator for some tumors. Integrin αvβ3 isparticularly attractive as a therapeutic target due to its relativelylimited cellular distribution. Integrin αvβ3 is not generally expressedon epithelial cells, and minimally expressed on other cell types.Furthermore, αvβ3 antagonists, including both cyclic RGD peptides andmonoclonal antibodies, significantly inhibit cytokine-inducedangiogenesis and the growth of solid tumor on the chick chorioallantoicmembrane.

Another integrin heterodimer, αvβ5, is more widely expressed onmalignant tumor cells and is likely involved in VEGF-mediatedangiogenesis. It has been shown that αvβ3 and αvβ5 promote angiogenesisvia distinct pathways: αvβ3 through bFGF and TNF-α, and αvβ5 throughVEGF and TGF-α. It has also been shown that inhibition of Src kinase canblock VEGF-induced, but not FGF2-induced, angiogenesis. These resultsstrongly imply that FGF2 and VEGF activate different angiogenic pathwaysthat require αvβ3 and αvβ5, respectively.

Integrins have also been implicated in tumor metastasis. Metastasis isthe primary cause of morbidity and mortality in cancer. Malignantprogression of melanoma, glioma, ovarian, and breast cancer have allbeen strongly linked with the expression of the integrin αvβ3 and insome cases with αvβ5. More recently, it has been shown that activationof integrin αvβ3 plays a significant role in metastasis in human breastcancer. A very strong correlation between expression of αvβ3 and breastcancer metastasis has been noted where normal breast epithelia are αvβ3negative and approximately 50% of invasive lobular carcinomas and nearlyall bone metastases in breast cancer express αvβ3. Antagonism of αvβ3with a cyclic peptide has been shown to synergize withradioimmunotherapy in studies involving breast cancer xenografts.

Angiogenesis, the formation of new blood vessels from existing ones, isessential to many physiological and pathological processes. Normally,angiogenesis is tightly regulated by pro- and anti-angiogenic factors,but in the case of diseases such as cancer, ocular neovascular disease,arthritis and psoriasis, the process can go awry. The association ofangiogenesis with disease has made the discovery of anti-angiogeniccompounds attractive. Among the most promising phage-derivedanti-angiogenic peptides described to date, are those that neutralizevascular endothelial growth factor (VEGF), and cytokine Ang2. See e.g.,U.S. Pat. Nos. 6,660,843 and 7,138,370 respectively.

While the VEGFs and their receptors have been among the most extensivelytargeted molecules in the angiogenesis field, preclinical effortstargeting the more recently discovered angiopoietin-Tie2 pathway areunderway. Both protein families involve ligand receptor interactions,and both include members whose functions are largely restrictedpostnatally to endothelial cells and some hematopoietic stem celllineages. Tie2 is a receptor tyrosine kinase with four known ligands,angiopoietin-1 (Ang1) through angiopoietin-4 (Ang4), the best studiedbeing Ang1 and Ang2. Ang1 stimulates phosphorylation of Tie2 and theAng2 interaction with Tie2 has been shown to both antagonize and agonizeTie2 receptor phosphorylation. Elevated Ang2 expression at sites ofnormal and pathological postnatal angiogenesis circumstantially impliesa proangiogenic role for Ang2. Vessel-selective Ang2 inductionassociated with angiogenesis has been demonstrated in diseases includingcancer. In patients with colon carcinoma, Ang2 is expressed ubiquitouslyin tumor epithelium, whereas expression of Ang1 in tumor epithelium hasbeen shown to be rare. The net gain of Ang2 activity has been suggestedto be an initiating factor for tumor angiogenesis.

Other proteins directed towards cellular receptors are under clinicalevaluation. HERCEPTIN® (Trastuzumab), developed by Genentech, is arecombinant humanized monoclonal antibody directed against theextracellular domain of the human epidermal tyrosine kinase receptor 2(HER2 or ErbB2). The HER2 gene is overexpressed in 25% of invasivebreast cancers, and is associated with poor prognosis and alteredsensitivity to chemotherapeutic agents. HERCEPTIN® blocks theproliferation of ErbB2-overexpressing breast cancers, and is currentlythe only ErbB2 targeted antibody therapy approved by the FDA for thetreatment of ErbB2 over-expressing metastatic breast cancer (MBC). Innormal adult cells, few ErbB2 molecules exist at the cell surface˜20,000 per cell thereby limiting their signaling capacity and thelikelihood of forming homo- and hetero-receptor complexes on the cellsurface. When ErbB2 is overexpressed on the cell surface, ˜500,000 percell, multiple ErbB2 homo- and hetero-complexes are formed and cellsignaling is stronger, resulting in enhanced responsiveness to growthfactors and malignant growth. This explains why ErbB2 overexpression isan indicator of poor prognosis in breast tumors and may be predictive ofresponse to treatment.

ErbB2 is a promising and validated target for breast cancer, where it isfound both in primary tumor and metastatic sites. HERCEPTIN® inducesrapid removal of ErbB2 from the cell surface, thereby reducing itsavailability to multimerize and ability to promote growth. Mechanisms ofaction of HERCEPTIN® observed in experimental in vitro and in vivomodels include inhibition of proteolysis of ErbB2's extracellulardomain, disruption of downstream signaling pathways such asphosphatidylinositiol 3-kinase (P13K) and mitogen-activated proteinkinase (MAPK) cascades, GI cell-cycle arrest, inhibition of DNA repair,suppression of angiogenesis and induction of antibody dependent cellularcytotoxicity (ADCC). Many patients with metastatic breast cancer whoinitially respond to HERCEPTIN®, however, demonstrate diseaseprogression within one year of treatment initiation.

Another target cellular receptor is type 1 insulin-like growth factor-1receptor (IGF1R), IGF1R is a receptor-tyrosine kinase that plays acritical role in signaling cell survival and proliferation. The IGFsystem is frequently deregulated in cancer cells by the establishment ofautocrine loops involving IGF-I or IGF-II and/or IGF1R overexpression.Moreover, epidemiological studies have suggested a link between elevatedIGF levels and the development of major human cancers, such as breast,colon, lung and prostate cancer. Expression of IGFs and their cognatereceptors has been correlated with disease stage, reduced survival,development of metastases and tumor de-differentiation.

Besides IGF1R, epidermal growth factor receptor (EGFR) has also beenimplicated in the tumorigenesis of numerous cancers. Effective tumorinhibition has been achieved both experimentally and clinically with anumber of strategies that antagonize either receptor activity. Becauseof the redundancy of growth signaling pathways in tumor cells,inhibition of one receptor function (e.g., EGFR) could be effectivelycompensated by up-regulation of other growth factor receptor (e.g.,IGF1R) mediated pathways. For example, a recent study has shown thatmalignant glioma cell lines expressing equivalent EGFR had significantlydifferent sensitivity to EGFR inhibition depending on their capabilityto activate IGF1R and its downstream signaling pathways. Other studieshave also demonstrated that overexpression and/or activation of IGF1R intumor cells might contribute to their resistance to chemotherapeuticagents, radiation, or antibody therapy such as HERCEPTIN®. Andconsequently, inhibition of IGF1R signaling has resulted in increasedsensitivity of tumor cells to HERCEPTIN®.

EGFR is a receptor tyrosine kinase that is expressed on many normaltissues as well as neoplastic lesions of most organs. Overexpression ofEGFR or expression of mutant forms of EGFR has been observed in manytumors, particularly epithelial tumors, and is associated with poorclinical prognosis. Inhibition of signaling through EGFR induces ananti-tumor effect. With the FDA approval of cetuximab, also known asERBITUX® (a mouse/human chimeric antibody) in February of 2004, EGFRbecame an approved antibody drug target for the treatment of metastaticcolorectal cancer. In March of 2006, ERBITUX® also received FDA approvalfor the treatment of squamous cell carcinoma of the head and neck(SCCHN). More recently, panitumumab, also known as VECTIBIX®, a fullyhuman antibody directed against EGFR, was approved for metastaticcolorectal cancer. Neither ERBITUX® or VECTIBIX® is a stand-alone agentin colorectal cancer—they were approved as add-ons to existingcolorectal regimens. In colorectal cancer, ERBITUX® is given incombination with the drug irinotecan and VECTIBIX® is administered afterdisease progression on, or following fluoropyrimidine-, oxaliplatin-,and irinotecan-containing chemotherapy regimens. ERBITUX® has beenapproved as a single agent in recurrent or metastatic SCCHN only whereprior platinum-based chemotherapy has failed. Advanced clinical trialswhich use these drugs to target non-small cell lung carcinoma areongoing. The sequence of the heavy and light chains of ERBITUX® are wellknown in the art (see for example, Goldstein, et al., Clin. Cancer Res.1:1311 (1995); U.S. Pat. No. 6,217,866, which are herein incorporated byreference).

An obstacle in the utilization of a catalytic antibody for selectiveprodrug activation in cancer therapy has been systemic tumor targeting.An efficient alternative would be using the catalytic antibody fused toa targeting peptide located outside the antibody combining site, therebyleaving the active site available for the prodrug activation asdescribed herein. For example, the fusion of Ab 38C2 to an integrinαvβ3-binding peptide would selectively localize the antibody to thetumor and/or the tumor vasculature and trigger prodrug activation atthat site. The potential therapy of this approach is supported bypreclinical and clinical data suggesting that peptides can be convertedinto viable drugs through attachment to the isolated Fc domain of animmunoglobulin. The present invention describes an approach based on theadaptation of target binding peptides, or modular recognition domains(MRDs), which are fused to full-length antibodies that effectivelytarget tumor cells or soluble molecules while retaining the prodrugactivation capability of the catalytic antibody. The current inventioncalls for the fusion of MRDs to the N- and/or C-termini of an antibody.So as not to significantly mitigate binding to the antibody'straditional binding site, the antibody's specificity remains intactafter MRD addition thereby resulting in a multi-specific antibody.

As depicted in FIG. 2, MRDs, designated by triangles, circles, diamonds,and squares, can be appended on any of the termini of either heavy orlight chains of a typical IgG antibody. The first schematic represents asimple peptibody with a peptide fused to the C-terminus of an Fc. Thisapproach provides for the preparation of bi-, tri-, tetra-, andpenta-specific antibodies. Display of a single MRD at each N- andC-termini of an IgG provides for octavalent display of the MRD. As analternative to the construction of bi- and multifunctional antibodiesthrough the combination of antibody variable domains, high-affinitypeptides selected from, for example, phage display libraries or derivedfrom natural ligands, may offer a highly versatile and modular approachto the construction of multifunctional antibodies that retain both thebinding and half-life advantages of traditional antibodies. MRDs canalso extend the binding capacity of non-catalytic antibodies, providingfor an effective approach to extend the binding functionality ofantibodies, particularly for therapeutic purposes.

Therapeutic antibodies represent the most rapidly growing sector of thepharmaceutical industry. Treatment with bispecific antibodies anddefined combinations of monoclonal antibodies are expected to showtherapeutic advantages over established and emerging antibodymonotherapy regimens. However, the cost of developing and producing suchtherapies has limited their consideration as viable treatments for mostindications. There is, therefore, a great need for developingmultispecific and multivalent antibodies having superior drug propertieswith substantially reduced production costs as compared to conventionalbispecific antibodies and combinations of monoclonal antibodies.

BRIEF SUMMARY OF THE INVENTION

The present invention is directed towards a full-length antibodycomprising at least one modular recognition domain (MRD). In someembodiments, the full-length antibody comprises multiple MRDs. Inadditional non-exclusive embodiments, the full-length antibody comprisesmore than one type of MRD (i.e. multiple MRDs having the same ordifferent specificities). Also embodied in the present invention arevariants and derivatives of such antibodies comprising a MRD. Variantsand derivatives of such antibodies comprising more than one type of MRDare also encompassed by the invention.

The MRDs of the MRD containing antibodies can be attached to theantibodies at any location on the antibody. In one aspect, the MRD isoperably linked to the C-terminal end of the heavy chain of theantibody. In another aspect, the MRD is operably linked to theN-terminal end of the heavy chain of the antibody. In yet anotheraspect, the MRD is operably linked to the C-terminal end of the lightchain of the antibody. In another aspect, the MRD is operably linked tothe N-terminal end of the light chain of the antibody. In anotheraspect, two or more MRDs are operably linked to the same antibodylocation, e.g., any terminal end of the antibody. In another aspect, twoor more MRDs are operably linked to at least two different antibodylocations, e.g., two or more different terminal ends of the antibody.

The antibodies of the MRD containing antibodies can be anyimmunoglobulin molecule that binds to an antigen and can be of any type,class, or subclass. In some embodiments, the antibody is an IgG. In someembodiments, the antibody is a polyclonal, monoclonal, multispecific,human, humanized, or chimeric antibody. In a specific embodiment, theantibody is chimeric or humanized. In another specific embodiment, theantibody is human. In other non-exclusive embodiments, the antibodiesalso include modifications that do not interfere with their ability tobind antigen.

In preferred embodiments, the antibody of the MRD-containing antibodybinds to a validated target. In one embodiment, the antibody binds to acell surface antigen. In another embodiment, the antibody binds to anangiogenic factor. In a further embodiment, the antibody binds to anangiogenic receptor.

In some embodiments, the antibody binds to a target that is selectedfrom the group consisting of EGFR, ErbB2, ErbB3, ErbB4, CD20,insulin-like growth factor-I receptor, VEGF, VEGF-R and prostatespecific membrane antigen.

In one specific embodiment, the antibody the antibody of theMRD-containing antibody binds to EGFR. In another specific embodiment,the antibody binds to the same epitope as Erbitux® antibody orcompetitively inhibits binding of the Erbitux® antibody to EGFR. In afurther specific embodiment, the antibody is the Erbitux® antibody.

In a specific embodiment, the antibody of the MRD-containing antibodybinds to ErbB2. In another specific embodiment, the antibody binds tothe same epitope as HERCEPTIN®. (trastuzumab) antibody or competitivelyinhibits HERCEPTIN®. (trastuzumab) antibody. In another specificembodiment, the antibody is an antibody that comprises the CDR sequencesof SEQ ID NOs: 59-64. In a further specific embodiment, the antibody isthe HERCEPTIN® (trastuzumab) antibody.

In another specific embodiment, the antibody binds to VEGF.

MRDs can be linked to an antibody or other MRDs directly or through alinker. A linker can be any chemical structure that allows for the MRDthat has been linked to an antibody to bind its target. In someembodiments, the linker is a chemical linker described herein orotherwise known in the art. In other embodiments the linker is apolypeptide linker described herein or otherwise known in the art. Inone aspect, the antibody and the MRD are operably linked through alinker peptide. In one aspect, the linker peptide is between 2 to 20peptides long, or between 4 to 10 or about 4 to 15 peptides long. In oneaspect, the linker peptide comprises the sequence GGGS (SEQ ID NO:1),the sequence SSGGGGSGGGGGGSS (SEQ ID NO:2), or the sequenceSSGGGGSGGGGGGSSRSS (SEQ ID NO:19). Other linkers containing a coresequence of GGGS as shown in SEQ ID NO:1 are also included hereinwherein the linker peptide is from about 4-20 amino acids.

The MRDs can be any target binding peptide. In some embodiments, the MRDtarget is a soluble factor. In other embodiments, the MRD target is atransmembrane protein such as a cell surface receptor. For example, insome embodiments, the MRD target is selected from the group consistingof an angiogenic cytokine and an integrin. In a specific embodiment, theMRD comprises the sequence of SEQ ID NO:8. In another specificembodiment, the MRD comprises the sequence of SEQ ID NO:14.

In one embodiment, the MRD is about 2 to 150 amino acids. In anotherembodiment, the MRD is about 2 to 60 amino acids.

In an additional embodiment, the MRD-containing antibody comprises anMRD containing a sequence selected from the group consisting of SEQ IDNO:8, and SEQ ID NO:14.

In other embodiments, the MRD binds to a target selected from the groupconsisting of: an integrin, a cytokine, an angiogenic cytokine, vascularendothelial growth factor (VEGF), insulin-like growth factor-I receptor(IGF-IR), a tumor antigen, CD20, an epidermal growth factor receptor(EGFR), the ErbB2 receptor, the ErbB3 receptor, tumor associated surfaceantigen epithelial cell adhesion molecule (Ep-CAM), an angiogenicfactor, an angiogenic receptor, cell surface antigen, soluble ligand,vascular homing peptide, and nerve growth factor

In other embodiments, the MRD binds to a target selected from the groupconsisting of: a cytokine, soluble ligand, VEGF receptor 1, and VEGFreceptor 2.

In one embodiment, the target of the MRD is a cellular antigen. In aspecific embodiment of the present invention, the target of the MRD isCD20.

In another embodiment, the target of the MRD is an integrin. In oneaspect, the peptide sequence of the integrin targeting MRD is YCRGDCT(SEQ ID NO:3). In another aspect, the peptide sequence of the integrintargeting MRD is PCRGDCL (SEQ ID NO:4). In yet another aspect, thepeptide sequence of the integrin targeting MRD is TCRGDCY (SEQ ID NO:5).In another aspect, the peptide sequence of the integrin targeting MRD isLCRGDCF (SEQ ID NO:6).

In an additional embodiment, the target of the MRD is an angiogeniccytokine. In one aspect, the peptide sequence of the angiogenic cytokinetargeting (i.e. binding) MRD is MGAQTNFMPMDDLEQRLYEQFILQQGLE (SEQ IDNO:7). In another aspect, the peptide sequence of the angiogeniccytokine targeting MRD is MGAQTNFMPMDNDELLLYEQFILQQGLE (SEQ ID NO:8). Inyet another aspect, the peptide sequence of the angiogenic cytokinetargeting MRD is MGAQTNFMPMDATE TRLYEQFILQQGLE (SEQ ID NO:9). In anotheraspect, the peptide sequence of the angiogenic cytokine targeting MRD isAQQEECEWDPWTCEHMGSGSATG GSGSTASSGSGSATHQEECEWDPWTCEHMLE (SEQ ID NO:10).In another aspect, the peptide sequence of the angiogenic cytokinetargeting MRD is MGAQTNFM PMDNDELLNYEQFILQQGLE (SEQ ID NO:11). Inanother aspect, the peptide sequence of the angiogenic cytokinetargeting MRD is PXDNDXLLNY (SEQ ID NO:12), where X is one of the 20naturally-occurring amino acids. In another aspect, the targeting MRDpeptide has the core sequence MGAQTNFMPMDXn (SEQ ID NO:56), wherein X isany amino acid and n is from about 0 to 15.

In a further embodiment, the targeting MRD peptide contains a coresequence selected from:

(SEQ ID NO: 22) XnEFAPWTXn where n is from about 0 to 50 aminoacid residues; (SEQ ID NO: 25)XnELAPWTXn where n is from about 0 to 50 amino acid residues;(SEQ ID NO: 28) XnEFSPWTXn where n is from about 0 to 50 aminoacid residues; (SEQ ID NO: 31)XnELEPWTXn where n is from about 0 to 50 amino acid residues;  and(SEQ ID NO: 57) XnAQQEECEX₁X₂PWTCEHMXn where n is from about 0 to50 amino acid residues and X, X₁ and X₂ are any amino acid.

Exemplary peptides containing such core peptides encompassed by theinvention include for example:

(SEQ ID NO: 21) AQQEECEFAPWTCEHM; (SEQ ID NO: 23)AQQEECEFAPWTCEHMGSGSATGGSGSTASSGSGSATHQEECEFAPWTCE HMLE; (SEQ ID NO: 24)AQQEECELAPWT CEHM; (SEQ ID NO: 26)AQQEECELAPWTCEHMGSGSATGGSGSTASSGSG SATHQEECELAPWTC EHMLE;(SEQ ID NO: 27) AQQEECEFSPWTCEHM; (SEQ ID NO: 29)AQQEECEFSPWTCEHMGSGSATGGSGSTASSGSGSATHQEECEFSPWT CEHMLE 2xConFS;(SEQ ID NO: 30) AQQEECELEPWTCEHM; (SEQ ID NO: 32)AQQEECELEPWTCEHMGSGSATGGSGSTASSGSGSATHQEECELEPWTCE HMLE; (SEQ ID NO: 33)AQQEECEFAPWTCEHMGSGSATGGSGSTASSGSGSATHQEEC ELAPWTC EHMLE;(SEQ ID NO: 34) AQQEECEFAPWTCEHMGSGSATGGSGSTA SSGSGSATHQEECEFSPWTCEHMLE; and (SEQ ID NO: 10)AQQEECEWDPWTCE HMGSGSATGGSGSTASSGSGSATHQEECEWDPWTC EHMLE.

In one embodiment, the target of the MRD is ErbB2. In anotherembodiment, the target to which the MRD binds is ErbB3. In an additionalembodiment, the target to which the MRD binds is tumor-associatedsurface antigen epithelial cell adhesion molecule (Ep-CAM).

In one embodiment, the target to which the MRD binds is VEGF. In oneaspect, the peptide sequence of the VEGF targeting MRD isVEPNCDIHVMWEWECFERL (SEQ ID NO:13).

In one embodiment, the target to which the MRD binds is an insulin-likegrowth factor-I receptor (IGF1R). In one aspect, the peptide sequence ofthe insulin-like growth factor-I receptor targeting MRD comprisesSFYSCLESLVNGPAEKSRGQWDGCRKK (SEQ ID NO:14). Other illustrative IGF1Rtargeting MRDs include, for example, a peptide sequence having theformula NFYQCIX₁X₂LX₃X₄X₅PAEKSRGQWQECRTGG (SEQ ID NO:58), wherein X₁ isE or D; X₂ is any amino acid; X₃ is any amino acid; X₄ is any aminoacid; and X₅ is any amino acid.

Illustrative peptides that contain such formula include:

(SEQ ID NO: 35) NFYQCIEMLASHPAEKSRGQWQECRTGG; (SEQ ID NO: 36)NFYQCIEQLALRPAEKSRGQWQECRTGG; (SEQ ID NO: 38)NFYQCIERLVTGPAEKSRGQWQECRTGG; (SEQ ID NO: 39)NFYQCIEYLAMKPAEKSRGQWQECRTGG; (SEQ ID NO: 40)NFYQCIEALQSRPAEKSRGQWQECRTGG; (SEQ ID NO: 41)NFYQCIEALSRSPAEKSRGQWQECRTGG; (SEQ ID NO: 42)NFYQCIEHLSGSPAEKSRGQWQECRTG; (SEQ ID NO: 43)NFYQCIESLAGGPAEKSRGQWQECRTG; (SEQ ID NO: 44)NFYQCIEALVGVPAEKSRGQWQECRTG; (SEQ ID NO: 45)NFYQCIEMLSLPPAEKSRGQWQECRTG; (SEQ ID NO: 46)NFYQCIEVFWGRPAEKSRGQWQECRTG; (SEQ ID NO: 47)NFYQCIEQLSSGPAEKSRGQWQECRTG; (SEQ ID NO: 48)NFYQCIELLSARPAEKSRGQWAECRAG; and (SEQ ID NO: 49)NFYQCIEALARTPAEKSRGQWVECRAP.

Other illustrative IGF1R targeting MRDs include, for example, a peptidesequence having the formula:

(SEQ ID NO: 37) NFYQCIDLLMAYPAEKSRGQWQECRTGG;

In one embodiment, the target of the MRD is a tumor antigen.

In one embodiment, the target of the MRD is an epidermal growth factorreceptor (EGFR). In another embodiment of the present invention, thetarget of the MRD is an angiogenic factor. In an additional embodiment,the target of the MRD is an angiogenic receptor.

In another embodiment, the MRD is a vascular homing peptide. In oneaspect, the peptide sequence of the vascular homing peptide MRDcomprises the sequence ACDCRGDCFCG (SEQ ID NO:15).

In one embodiment, the target of the MRD is a nerve growth factor.

In another embodiment, the antibody and/or MRD binds to EGFR, ErbB2,ErbB3, ErbB4, CD20, insulin-like growth factor-I receptor, or prostatespecific membrane antigen.

In one aspect, the peptide sequence of the EGFR targeting (binding) MRDis VDNKFNKELEKAYNEIRNLPNLNGWQMTAFIASLVDDPSQSANLLAEAKKLNDAQAPK (SEQ IDNO:16). In one aspect, the peptide sequence of the EGFR targeting MRD isVDNKFNKEMWIAWEEIRNLPNLNGWQMTAFIASLVDDPSQSANLLAEA KKLNDAQAPK (SEQ IDNO:17). In another aspect, the peptide sequence of the ErbB2 targetingMRD is VDNKFNKEMRNAYWEIALLPNLNNQQKRAFIRSLYDDPSQSA NLLAEAKKLNDAQAPK (SEQID NO:18).

The present invention also relates to an isolated polynucleotidecomprising a nucleotide sequence encoding an MRD containing antibody. Inone aspect, a vector comprises a polynucleotide sequence encoding an MRDcontaining antibody. In another aspect, the polynucleotide sequenceencoding an MRD containing antibody is operatively linked with aregulatory sequence that controls expression on the polynucleotide. Inan additional aspect, a host cell comprises the polynucleotide sequenceencoding an MRD containing antibody.

Methods of making MRD-antibody fusions (i.e. MRD-containing antibodies)are also provided, as are the use of these MRD-antibody fusions indiagnostic and therapeutic applications. The present invention alsorelates to methods of designing and making MRD-containing antibodieshaving a full-length antibody comprising a MRD. In one aspect, the MRDis derived from a phage display library. In another aspect, the MRD isderived from natural ligands. In another aspect, the MRD is derived fromyeast display or RNA display technology.

The present invention also relates to a method of treating or preventinga disease or disorder in a subject in need thereof, comprisingadministering an antibody comprising an MRD to the subject. In oneaspect, the disease is cancer. In another aspect, undesired angiogenesisin inhibited. In another aspect, angiogenesis is modulated. In yetanother aspect, tumor growth is inhibited.

Certain embodiments provide for methods of treating or preventing adisease, disorder, or injury comprising administering a therapeuticallyeffective amount of an antibody comprising an MRD (i.e. MRD-containingantibodies) to a subject in need thereof. In some embodiments, thedisease, disorder or injury is cancer.

In another embodiment, a method of treatment or prevention comprisingadministering an additional therapeutic agent along with an antibodycomprising an MRD is provided. In other embodiments, the methods oftreatment or prevention comprise administering an antibody comprisingmore than one type of MRD.

BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES

FIG. 1 shows the schematic representation of different designs ofmulti-specific and multi-valent molecules. MRDs are depicted astriangles, circles, diamonds, and squares.

FIG. 2A shows a typical peptibody as a C-terminal fusion with the heavychain of Fc.

FIG. 2B shows an MRD containing antibody with a C-terminal MRD fusionwith the light chain of the antibody.

FIG. 2C shows an MRD containing antibody with an N-terminal MRD fusionwith the light chain of the antibody.

FIG. 2D shows an MRD containing antibody with unique MRD peptides fusedto each terminus of the antibody.

FIG. 3 depicts the results of an enzyme linked immunosorbent assay(ELISA) in which integrin and Ang2 were bound by an anti-integrinantibody (JC7U) fused to a Ang2 targeting MRD (2xCon4).

FIG. 4 depicts the results of an ELISA in which integrin and Ang2 werebound by an anti-integrin antibody (JC7U) fused to a Ang2 targeting MRD(2xCon4).

FIG. 5 depicts the results of an ELISA in which an anti-ErbB2 antibodywas fused to an MRD which targets Ang2.

FIG. 6 depicts the results of an ELISA in which an Ang2 targeting MRDwas fused to a hepatocyte growth factor receptor (cMET) bindingantibody.

FIG. 7 depicts the results of an ELISA in which an integrin targetingMRD was fused to an ErbB2 binding antibody.

FIG. 8 depicts the results of an ELISA in which an integrin targetingMRD was fused to an hepatocyte growth factor receptor binding antibody.

FIG. 9 depicts the results of an ELISA in which an insulin-like growthfactor-I receptor targeting MRD was fused to an ErbB2 binding antibody.

FIG. 10 depicts the results of an ELISA in which a VEGF-targeting MRDwas fused to an ErbB2 binding antibody.

FIG. 11 depicts the results of an ELISA in which an integrin targetingMRD was fused to a catalytic antibody.

FIG. 12 depicts the results of an ELISA in which an Ang2-targeting MRDwas fused to a catalytic antibody.

FIG. 13 depicts the results of an ELISA in which an integrin targetingMRD and an Ang2 targeting MRD were fused to an ErbB2 binding antibody.

FIG. 14 depicts the results of an ELISA in which an integrin targetingMRD was fused to an ErbB2 binding antibody.

FIG. 15 depicts the results of an ELISA in which an integrin, Ang2, orinsulin-like growth factor-I receptor-targeting MRD was fused to anErbB2 or hepatocyte growth factor receptor-binding antibody with a shortlinker peptide.

FIG. 16 depicts the results of an ELISA in which an integrin, Ang2, orinsulin-like growth factor-I receptor-targeting MRD was fused to anErbB2 or hepatocyte growth factor receptor-binding antibody with a longlinker peptide.

FIG. 17A depicts the results of an assay for direct binding of aHERCEPTIN® based zybody (i.e. an MRD containing HERCEPTIN® antibodysequences) antibody-MRDs and a HERCEPTIN® antibody to Her2 (ErbB2) Fc inthe presence of biotinylated Ang2. Binding was detected withHRP-conjugated anti-human kappa chain mAb.

FIG. 17B depicts the results of an assay for direct binding of aHERCEPTIN® based zybody (i.e., an MRD containing HERCEPTIN® antibodysequences) and a HERCEPTIN® antibody to Her2 Fc in the presence ofbiotinylated Ang2. Binding was detected with horseradish peroxidase(HRP)-conjugated streptavidin.

FIG. 18A depicts the results of a flow cytometry assay whichdemonstrates that antibody-MRDs simultaneously bind Her2 and Ang2 onBT-474 breast cancer cells.

FIG. 18B depicts binding of antibody-MRDs to HER2 on BT-474 breastcancer cells.

FIG. 19 depicts the results of an ELISA assay that demonstrates theinhibitory effect of antibody-MRDs on TIE-2 binding to plate immobilizedAng2.

FIG. 20 depicts the results of a competitive binding assay thatdemonstrates the inhibition of binding of biotinylated antibody byantibody-MRD and unlabeled antibody.

FIG. 21 depicts the results of a competitive binding assay thatillustrates the inhibition of labeled antibody binding to BT-474 cellsby antibody-MRDs and unlabeled antibody.

FIG. 22A depicts the fitted dose curves illustrating the inhibition ofBT-474 cell proliferation by HERCEPTIN® with the Im32 MRD (SEQ ID NO:8)fused to the heavy chain and HERCEPTIN®.

FIG. 22B depicts the fitted dose curves illustrating the inhibition ofBT-474 cell proliferation by HERCEPTIN® with the Im32 MRD fused to thelight chain and HERCEPTIN®.

FIG. 22C depicts the fitted dose curves illustrating the inhibition ofBT-474 cell proliferation by HERCEPTIN® with the 2xcon4 MRD fused to theheavy chain and HERCEPTIN®.

FIG. 23A depicts the results of a cytotoxicity assay illustratingADCC-mediated killing of BT-474 cells by HERCEPTIN® with the Im32 MRDfused to the heavy chain, HERCEPTIN® with the Im32 MRD fused to thelight chain, and HERCEPTIN®.

FIG. 23B depicts the results of a cytotoxicity assay illustratingADCC-mediated killing of BT-474 cells by HERCEPTIN® with the 2xcon4 MRDfused to the heavy chain, and HERCEPTIN®.

FIG. 24 depicts the effect of RITUXIMAB®, HERCEPTIN®, and anMRD-containing antibody on tumor volume in vivo.

DETAILED DESCRIPTION OF THE INVENTION

The following provides a description of antibodies containing at leastone modular recognition domain (MRD). The linkage of one or more MRDs toan antibody results in a multi-specific molecule of the invention thatretains structural and functional properties of traditional antibodiesor Fc optimized antibodies and can readily be synthesized usingconventional antibody expression systems and techniques. The antibodycan be any suitable antigen-binding immunoglobulin, and the MRDs can beany suitable target-binding peptide. The MRDs can be operably linked toany location on the antibody, and the attachment can be direct orindirect (e.g., through a chemical or polypeptide linker). Compositionsof antibodies comprising an MRD, methods of manufacturing antibodiescomprising an MRD, and methods of using antibodies comprising MRDs arealso described in the sections below.

The section headings used herein are for organizational purposes onlyand are not to be construed as in any way limiting the subject matterdescribed.

Standard techniques may be used for recombinant DNA molecule, protein,and antibody production, as well as for tissue culture and celltransformation. Enzymatic reactions and purification techniques aretypically performed according to the manufacturer's specifications or ascommonly accomplished in the art using conventional procedures such asthose set forth in Harlow et al., Antibodies: A Laboratory Manual, (ColdSpring Harbor Laboratory Press, 2nd ed. 1988) and Sambrook et al.(Molecular Cloning: A Laboratory Manual. Cold Spring Harbor LaboratoryPress, Cold Spring Harbor, N.Y. (1989)) (both herein incorporated byreference), or as described herein. Unless specific definitions areprovided, the nomenclature utilized in connection with, and thelaboratory procedures and techniques of analytical chemistry, syntheticorganic chemistry, and medicinal and pharmaceutical chemistry describedherein, are those known and used in the art. Standard techniques may beused for chemical syntheses, chemical analyses, pharmaceuticalpreparation, formulation, delivery, and treatment of patients.

I. DEFINITIONS

The terms “MRD-containing antibodies,” “antibody-MRD molecules,”“MRD-antibody molecules,” “antibodies comprising an MRD” and “Zybodies”are used interchangeably herein and do not encompass a peptibody. Eachof these terms may also be used herein to refer to a “complex” of theinvention.

The term “antibody” is used herein to refer to immunoglobulin moleculesthat are able to bind antigens through an antigen binding domain (i.e.,antibody combining site). The term “antibody” includes polyclonal,oligoclonal (mixtures of antibodies), and monoclonal antibodies,chimeric, single chain, and humanized antibodies. The term “antibody”also includes human antibodies. In some embodiments, an antibodycomprises at least two heavy (H) chains and two light (L) chainsinter-connected by disulfide bonds. Each heavy chain is comprised of aheavy chain variable region (abbreviated herein as VH) and a heavy chainconstant region. The heavy chain constant region is comprised of threedomains: CH1, CH2, and CH3. Each light chain is comprised of a lightchain variable region (abbreviated herein as VL) and a light chainconstant region. The light chain constant region is comprised of onedomain, CL. The VH and VL regions can be further subdivided into regionsof hypervariability, termed complementarity determining regions (CDR),interspersed with regions that are more conserved, termed frameworkregions (FR). Each VH and VL is composed of three CDRs and four FRs,arranged from amino-terminus to carboxyl-terminus in the followingorder: FR1, CDR1, FR2, CDR2, FR3, CDR3, FR4. In other embodiments, theantibody is a homomeric heavy chain antibody (e.g., camelid antibodies)which lacks the first constant region domain (CH1) but retains anotherwise intact heavy chain and is able to bind antigens through anantigen binding domain. The variable regions of the heavy and lightchains in the antibody-MRD fusions of the invention contain a functionalbinding domain that interacts with an antigen.

The term “monoclonal antibody” typically refers to a population ofantibody molecules that contain only one species of antibody combiningsite capable of immunoreacting with a particular epitope. A monoclonalantibody thus typically displays a single binding affinity for anyepitope with which it immunoreacts. As used herein, a “monoclonalantibody” may also contain an antibody molecule having a plurality ofantibody combining sites (i.e., a plurality of variable domains), eachimmunospecific for a different epitope, e.g., a bispecific monoclonalantibody. Thus, as used herein, a “monoclonal antibody” refers to ahomogeneous antibody population involved in the highly specificrecognition and binding of one or two (in the case of a bispecificmonoclonal antibody) antigenic determinants, or epitopes. This is incontrast to polyclonal antibodies that typically include differentantibodies directed against different antigenic determinants. The term“monoclonal antibody” refers to such antibodies made in any number ofmanners including but not limited to by hybridoma, phage selection,recombinant expression, yeast, and transgenic animals.

A “dual-specific antibody” is used herein to refer to an immunoglobulinmolecule that contains dual-variable-domain immunoglobulins, where thedual-variable-domain can be engineered from any two monoclonalantibodies.

The term “chimeric antibodies” refers to antibodies wherein the aminoacid sequence of the immunoglobulin molecule is derived from two or morespecies. Typically, the variable region of both light and heavy chainscorresponds to the variable region of antibodies derived from onespecies of mammals (e.g., mouse, rat, rabbit, etc.) with the desiredspecificity and/or affinity while the constant regions are homologous tothe sequences in antibodies derived from another species (usually human)to avoid eliciting an immune response in that species.

The term “humanized antibody” refers to forms of non-human (e.g.,murine) antibodies that are specific immunoglobulin chains, chimericimmunoglobulins, or fragments thereof that contain minimal non-human(e.g., murine) sequences. Typically, humanized antibodies are humanimmunoglobulins in which residues from the complementarity determiningregion (CDR) are replaced by residues from the CDR of a non-humanspecies (e.g., mouse, rat, rabbit, hamster) that have the desiredspecificity and/or affinity (Jones et al., Nature, 321:522-525 (1986);Riechmann et al., Nature, 332:323-327 (1988); Verhoeyen et al., Science,239:1534-1536 (1988)). In some instances, the Fv framework region (FR)residues of a human immunoglobulin are replaced with the correspondingresidues in an antibody from a non-human species that has the desiredspecificity and/or affinity. The humanized antibody can be furthermodified by the substitution of additional residues either in the Fvframework region and/or within the replaced non-human residues to refineand optimize antibody specificity, affinity, and/or capability. Ingeneral, the humanized antibody will comprise substantially all of atleast one, and typically two or three, variable domains containing allor substantially all of the CDR regions that correspond to the non-humanimmunoglobulin whereas all or substantially all of the FR regions arethose of a human immunoglobulin consensus sequence. The humanizedantibody can also comprise an immunoglobulin constant region or domain(Fc), typically that of a human immunoglobulin. Examples of methods usedto generate humanized antibodies are described in U.S. Pat. No.5,225,539, U.S. Pat. No. 4,816,567, Morrison, Science 229:1202 (1985);Oi et al., BioTechniques 4:214 (1986); Cabilly et al., Taniguchi et al.,EP 171496; Morrison et al., EP 173494; Neuberger et al., WO 86/01533;Robinson et al., WO 8702671; Boulianne et al., Nature 312:643 (1984);and Neuberger et al., Nature 314:268 (1985) which are hereinincorporated by reference.

As used herein, “human” antibodies include antibodies having the aminoacid sequence of a human immunoglobulin or one or more human germlinesand include antibodies isolated from human immunoglobulin libraries orfrom animals transgenic for one or more human immunoglobulins and thatdo not express endogenous immunoglobulins, as described infra and, forexample in, U.S. Pat. No. 5,939,598 by Kucherlapati et al. A humanantibody may still be considered “human” even if amino acidsubstitutions are made in the antibody. Examples of methods used togenerate human antibodies are described in: PCT publications WO98/24893, WO 92/01047, WO 96/34096, and WO 96/33735; European Patent No.0 598 877; U.S. Pat. Nos. 5,413,923, 5,625,126, 5,633,425, 5,569,825,5,661,016, 5,545,806, 5,814,318, 5,885,793, 5,916,771, and 5,939,598;and Lonberg and Huszar, Int. Rev. Immunol. 13:65-93 (1995), which areherein incorporated by reference.

An “antibody combining site” is that structural portion of an antibodymolecule comprised of heavy and light chain variable and hypervariableregions that specifically binds (immunoreacts with) an antigen. The term“immunoreact” in its various forms means specific binding between anantigenic determinant-containing molecule and a molecule containing anantibody combining site such as a whole antibody molecule or a portionthereof.

In naturally occurring antibodies, the six “complementarity determiningregions” or “CDRs” present in each antigen binding domain are short,non-contiguous sequences of amino acids that are specifically positionedto form the antigen binding domain as the antibody assumes its threedimensional configuration in an aqueous environment. The remainder ofthe amino acids in the antigen binding domains, referred to as“framework” regions, show less inter-molecular variability. Theframework regions largely adopt a β-sheet conformation and the CDRs formloops which connect, and in some cases form part of, the β-sheetstructure. Thus, framework regions act to form a scaffold that providesfor positioning the CDRs in correct orientation by inter-chain,non-covalent interactions. The antigen binding domain (i.e., antibodycombining site) formed by the positioned CDRs defines a surfacecomplementary to the epitope on the immunoreactive antigen. Thiscomplementary surface promotes the non-covalent binding of the antibodyto its cognate epitope. The amino acids comprising the CDRs and theframework regions, respectively, can be readily identified for any givenheavy or light chain variable region by one of ordinary skill in theart, since they have been precisely defined (see, “Sequences of Proteinsof Immunological Interest,” Kabat, E., et al., U.S. Department of Healthand Human Services, (1983); and Chothia and Lesk, J. Mol. Biol.,196:901-917 (1987), which are herein incorporated by reference).“Humanized antibody” or “chimeric antibody” includes antibodies in whichCDR sequences derived from the germline of another mammalian species,such as a mouse, have been grafted onto human framework sequences.

The term “peptibody” refers to a peptide or polypeptide which comprisesless than a complete, intact antibody. A peptibody can be an antibody Fcdomain attached to at least one peptide. A peptibody does not includeantibody variable regions, an antibody combining site, CH1 domains, orIg light chain constant region domains.

The term “naturally occurring” when used in connection with biologicalmaterials such as a nucleic acid molecules, polypeptides, host cells,and the like refers to those which are found in nature and not modifiedby a human being.

The term “domain” as used herein refers to a part of a molecule orstructure that shares common physical or chemical features, for examplehydrophobic, polar, globular, helical domains or properties, e.g., aprotein binding domain, a DNA binding domain or an ATP binding domain.Domains can be identified by their homology to conserved structural orfunctional motifs.

A “conservative amino acid substitution” is one in which one amino acidresidue is replaced with another amino acid residue having a similarside chain. Families of amino acid residues having similar side chainshave been defined in the art, including basic side chains (e.g., lysine,arginine, histidine), acidic side chains (e.g., aspartic acid, glutamicacid), uncharged polar side chains (e.g., glycine, asparagine,glutamine, serine, threonine, tyrosine, cysteine), nonpolar side chains(e.g., alanine, valine, leucine, isoleucine, proline, phenylalanine,methionine, tryptophan), beta-branched side chains (e.g., threonine,valine, isoleucine) and aromatic side chains (e.g., tyrosine,phenylalanine, tryptophan, histidine). For example, substitution of aphenylalanine for a tyrosine is a conservative substitution. In someembodiments, conservative substitutions in the sequences of thepolypeptides and antibodies of the invention do not abrogate the bindingof the polypeptide or antibody containing the amino acid sequence to theantigen(s) to which the polypeptide or antibody binds. Methods ofidentifying nucleotide and amino acid conservative substitutions andnon-conservative substitutions which do not eliminate polypeptide orantigen binding are well-known in the art (see, e.g., Brummell et al.,Biochem. 32:1180-1187 (1993); Kobayashi et al., Protein Eng.12(10):879-884 (1999); and Burks et al., Proc. Natl. Acad. Sci. USA94:412-417 (1997)).

A “modular recognition domain” (MRD) or “target binding peptide” is amolecule, such as a protein, glycoprotein and the like, that canspecifically (non-randomly) bind to a target molecule. The amino acidsequence of a MRD can typically tolerate some degree of variability andstill retain a degree of capacity to bind the target molecule.Furthermore, changes in the sequence can result in changes in thebinding specificity and in the binding constant between a preselectedtarget molecule and the binding site. In one embodiment, the MRD is anagonist of the target it binds. An MRD agonist refers to a MRD that insome way increases or enhances the biological activity of the MRD'starget protein or has biological activity comparable to a known agonistof the MRD's target protein. In another embodiment, the MRD is anantagonist of the target it binds. An MRD antagonist refers to an MRDthat blocks or in some way interferes with the biological activity ofthe MRD's target protein or has biological activity comparable to aknown antagonist or inhibitor of the MRD's target protein.

“Cell surface receptor” refers to molecules and complexes of moleculescapable of receiving a signal and the transmission of such a signalacross the plasma membrane of a cell. An example of a cell surfacereceptor of the present invention is an activated integrin receptor, forexample, an activated αvβ3 integrin receptor on a metastatic cell. Asused herein, “cell surface receptor” also includes a molecule expressedon a cell surface that is capable of being bound by an MRD containingantibody of the invention.

As used herein, a “target binding site” or “target site” is any known,or yet to be defined, amino acid sequence having the ability toselectively bind a preselected agent. Exemplary reference target sitesare derived from the RGD-dependent integrin ligands, namely fibronectin,fibrinogen, vitronectin, von Willebrand factor and the like, fromcellular receptors such as ErbB2, VEGF, vascular homing peptide orangiogenic cytokines, from protein hormones receptors such asinsulin-like growth factor-I receptor, epidermal growth factor receptorand the like, and from tumor antigens.

The term “epitope” or “antigenic determinant” are used interchangeablyherein and refer to that portion of any molecule capable of beingrecognized and specifically bound by a particular binding agent (e.g.,an antibody or an MRD). When the recognized molecule is a polypeptide,epitopes can be formed from contiguous amino acids and noncontiguousamino acids and/or other chemically active surface groups of molecules(such as carbohydrates) juxtaposed by tertiary folding of a protein.Epitopes formed from contiguous amino acids are typically retained uponprotein denaturing, whereas epitopes formed by tertiary folding aretypically lost upon protein denaturing. An epitope typically includes atleast 3, and more usually, at least 5 or 8-10 amino acids in a uniquespatial conformation.

An antibody, MRD, antibody-containing MRD, or other molecule is said to“competitively inhibit” binding of a reference molecule to a givenepitope if it binds to that epitope to the extent that it blocks, tosome degree, binding of the reference molecule to the epitope.Competitive inhibition may be determined by any method known in the art,for example, competition ELISA assays. As used herein, an antibody, MRD,antibody-containing MRD, or other molecule may be said to competitivelyinhibit binding of the reference molecule to a given epitope, forexample, by at least 90%, at least 80%, at least 70%, at least 60%, orat least 50%.

The term “protein” is defined as a biological polymer comprising unitsderived from amino acids linked via peptide bonds; a protein can becomposed of two or more chains.

A “fusion polypeptide” is a polypeptide comprised of at least twopolypeptides and optionally a linking sequence to operatively link thetwo polypeptides into one continuous polypeptide. The two polypeptideslinked in a fusion polypeptide are typically derived from twoindependent sources, and therefore a fusion polypeptide comprises twolinked polypeptides not normally found linked in nature. The twopolypeptides may be operably attached directly by a peptide bond or maybe linked indirectly through a linker described herein or otherwiseknown in the art.

The term “operably linked,” as used herein, indicates that two moleculesare attached so as to each retain functional activity. Two molecules are“operably linked” whether they are attached directly (e.g., a fusionprotein) or indirectly (e.g., via a linker).

The term “linker” refers to a peptide located between the antibody andthe MRD or between two MRDs. Linkers can have from about 1 to 20 aminoacids, about 2 to 20 amino acids, or about 4 to 15 amino acids. One ormore of these amino acids may be glycosylated, as is well understood bythose in the art. In one embodiment, the 1 to 20 amino acids areselected from glycine, alanine, proline, asparagine, glutamine, andlysine. In another embodiment, a linker is made up of a majority ofamino acids that are sterically unhindered, such as glycine and alanine.Thus, in some embodiments, the linker is selected from polyglycines(such as (Gly)_(s), and (Gly)_(s)), poly(Gly-Ala), and polyalanines. Thelinker can also be a non-peptide linker such as an alkyl linker, or aPEG linker. For example, alkyl linkers such as —NH—(CH₂)s—C(O)—, whereins=2-20 can be used. These alkyl linkers may further be substituted byany non-sterically hindering group such as lower alkyl (e.g., C₁-C₆)lower acyl, halogen (e.g., Cl, Br), CN, NH₂, phenyl, etc. An exemplarynon-peptide linker is a PEG linker. In certain embodiments, the PEGlinker has a molecular weight of about 100 to 5000 kDa, or about 100 to500 kDa. The peptide linkers may be altered to form derivatives.

“Target cell” refers to any cell in a subject (e.g., a human or animal)that can be targeted by an antibody-containing MRD or MRD of theinvention. The target cell can be a cell expressing or overexpressingthe target binding site, such as an activated integrin receptor.

“Patient,” “subject,” “animal” or “mammal” are used interchangeably andrefer to mammals such as human patients and non-human primates, as wellas experimental animals such as rabbits, rats, and mice, and otheranimals. Animals include all vertebrates, e.g., mammals and non-mammals,such as sheep, dogs, cows, chickens, amphibians, and reptiles. In someembodiments, the patient is a human.

“Treating” or “treatment” includes the administration of the antibodycomprising an MRD of the present invention to prevent or delay the onsetof the symptoms, complications, or biochemical indicia of a disease,condition, or disorder, alleviating the symptoms or arresting orinhibiting further development of the disease, condition, or disorder.Treatment can be prophylactic (to prevent or delay the onset of thedisease, or to prevent the manifestation of clinical or subclinicalsymptoms thereof) or therapeutic suppression or alleviation of symptomsafter the manifestation of the disease, condition, or disorder.Treatment can be with the antibody-MRD composition alone, the MRD alone,or in combination of either with an additional therapeutic agent.

As used herein, the terms “pharmaceutically acceptable,” or“physiologically tolerable” and grammatical variations thereof, as theyrefer to compositions, carriers, diluents and reagents, are usedinterchangeably and represent that the materials are capable ofadministration to or upon a human without the production oftherapeutically prohibitive undesirable physiological effects such asnausea, dizziness, gastric upset and the like.

“Modulate,” means adjustment or regulation of amplitude, frequency,degree, or activity. In another related aspect, such modulation may bepositively modulated (e.g., an increase in frequency, degree, oractivity) or negatively modulated (e.g., a decrease in frequency,degree, or activity).

“Cancer,” “tumor,” or “malignancy” are used as synonymous terms andrefer to any of a number of diseases that are characterized byuncontrolled, abnormal proliferation of cells, the ability of affectedcells to spread locally or through the bloodstream and lymphatic systemto other parts of the body (metastasize) as well as any of a number ofcharacteristic structural and/or molecular features. A “canceroustumor,” or “malignant cell” is understood as a cell having specificstructural properties, lacking differentiation and being capable ofinvasion and metastasis. Examples of cancers that may be treated usingthe antibody-MRD fusions of the invention include breast, lung, brain,bone, liver, kidney, colon, head and neck, ovarian, hematopoietic (e.g.,leukemia), and prostate cancer. Other types of cancer and tumors thatmay be treated using MRD-containing antibodies are described herein orotherwise known in the art.

An “effective amount” of an antibody, MRD, or MRD-containing antibody asdisclosed herein is an amount sufficient to carry out a specificallystated purpose such as to bring about an observable change in the levelof one or more biological activities related to the target to which theantibody, MRD, or MRD-containing antibody binds. In certain embodiments,the change increases the level of target activity. In other embodiments,the change decreases the level of target activity. An “effective amount”can be determined empirically and in a routine manner, in relation tothe stated purpose.

The term “therapeutically effective amount” refers to an amount of anantibody, MRD, MRD-containing antibody, or other drug effective to“treat” a disease or disorder in a subject or mammal. In the case ofcancer, the therapeutically effective amount of the drug can reduceangiogenesis and neovascularization; reduce the number of cancer cells;reduce the tumor size; inhibit (i.e., slow to some extent or stop)cancer cell infiltration into peripheral organs; inhibit (i.e., slow tosome extent or stop) tumor metastasis; inhibit, to some extent, tumorgrowth or tumor incidence; stimulate immune responses against cancercells and/or relieve to some extent one or more of the symptomsassociated with the cancer. See the definition herein of “treating”. Tothe extent the drug can prevent growth and/or kill existing cancercells, it can be cytostatic and/or cytotoxic. A “prophylacticallyeffective amount” refers to an amount effective, at dosages and forperiods of time necessary, to achieve the desired prophylactic result.Typically, but not necessarily, since a prophylactic dose is used insubjects prior to or at an earlier stage of disease, theprophylactically effective amount will be less than the therapeuticallyeffective amount.

II. MODULAR RECOGNITION DOMAINS (MRDS)

The present invention describes an approach based on the adaptation oftarget binding peptides or modular recognition domains (MRDs) as fusionsto catalytic or non-catalytic antibodies.

In certain embodiments, where the antibody component of the MRD-antibodyfusion is a catalytic antibody, the MRD-antibody fusions provide foreffective targeting to tumor cells or soluble molecules while leavingthe prodrug activation capability of the catalytic antibody intact. MRDscan also extend the binding capacity of non-catalytic antibodiesproviding for an effective approach to extend the binding functionalityof antibodies, particularly for therapeutic purposes.

One aspect of the present invention relates to development of afull-length antibody comprising at least one modular recognition domain(MRD). In another non-exclusive embodiment, the full-length antibodycomprises more than one MRD, wherein the MRDs have the same or differentspecificities. In addition, a single MRD may be comprised of a tandemrepeat of the same or different amino acid sequence that can allow forthe binding of a single MRD to multiple targets.

The interaction between a protein ligand and its target receptor siteoften takes place at a relatively large interface. However, only a fewkey residues at the interface contribute to most of the binding. TheMRDs can mimic ligand binding. In certain embodiments, the MRD can mimicthe biological activity of a ligand (an agonist MRD) or throughcompetitive binding inhibit the bioactivity of the ligand (an antagonistMRD). MRDs in MRD-containing antibodies can also affect targets in otherways, e.g., by neutralizing, blocking, stabilizing, aggregating, orcrosslinking the MRD target.

It is contemplated that MRDs of the present invention will generallycontain a peptide sequence that binds to target sites of interests andhave a length of about 2 to 150 amino acids, about 2 to 125 amino acids,about 2 to 100 amino acids, about 2 to 90 amino acids, about 2 to 80amino acids, about 2 to 70 amino acids, about 2 to 60 amino acids, about2 to 50 amino acids, about 2 to 40 amino acids, about 2 to 30 amino,acids, or about 2 to 20 amino acids. It is also contemplated that MRDshave a length of about 10 to 150 amino acids, about 10 to 125 aminoacids, about 10 to 100 amino acids, about 10 to 90 amino acids, about 10to 80 amino acids, about 10 to 70 amino acids, about 10 to 60 aminoacids, about 10 to 50 amino acids, about 10 to 40 amino acids, about 10to 30 amino acids, or about 10 to 20 amino acids. It is furthercontemplated that MRDs have a length of about 20 to 150 amino acids,about 20 to 125 amino acids, about 20 to 100 amino acids, about 20 to 90amino acids, about 20 to 80 amino acids, about 20 to 70 amino acids,about 20 to 60 amino acids, about 20 to 50 amino acids, about 20 to 40amino acids, or about 20 to 30 amino acids. In certain embodiments, theMRDs have a length of about 2 to 60 amino acids. In other embodiments,the MRDs have a length of about 10 to 60 amino acids. In otherembodiments, the MRDs have a length of about 10 to 50 amino acids. Inadditional embodiments, the MRDs have a length of about 10 to 40 aminoacids. In additional embodiments, the MRDs have a length of about 10 to30 amino acids.

In nonexclusive embodiments, the MRD does not contain an antigen bindingdomain, or another antibody domain such as a constant region, a variableregion, a complementarity determining region (CDR), a framework region,an Fc domain, or a hinge region. In one non-exclusive embodiment, theMRD does not contain an antigen binding domain. In another non-exclusiveembodiment, the MRD does not contain three CDRs. In anothernon-exclusive embodiment, the MRD does not contain CDR1 and CDR2. In yetanother non-exclusive embodiment, the MRD does not contain CDR1. In onenonexclusive embodiment, the MRD is not derived from a natural cellularligand. In another nonexclusive embodiment, the MRD is not aradioisotope. In another nonexclusive embodiment, the MRD is not aprotein expression marker such as glutathione S-transferase (GST),His-tag, Flag, hemagglutinin (HA), MYC or a fluorescent protein (e.g.,GFP or RFP). In another nonexclusive embodiment, the MRD does not bindserum albumin. In an additional nonexclusive embodiment, the MRD is nota small molecule that is a cytotoxin. It yet another nonexclusiveembodiment, the MRD does not have enzymatic activity. In anothernon-exclusive embodiment, the MRD has a therapeutic effect whenadministered alone and/or when fused to an Fc in a patient or animalmodel. In another non-exclusive embodiment, the MRD has a therapeuticeffect when repeatedly administered alone and/or when fused to an Fc ina patient or animal model (e.g., 3 or more times over the course of atleast six months).

In some embodiments, the MRD is conformationally constrained. In otherembodiments, the MRD is not conformationally constrained.

In some particular embodiments, the MRD has a particular hydrophobicity.For example, the hydrophobicity of MRDs can be compared on the basis ofretention times determined using hydrophobic interaction chromatographyor reverse phase liquid chromatography.

The MRD target can be any molecule that it is desirable for anMRD-containing antibody to interact with. For example, the MRD targetcan be a soluble factor or a transmembrane protein, such as a cellsurface receptor. In certain non-exclusive embodiments, the MRD targetis a factor that regulates cell proliferation, differentiation, orsurvival. In other nonexclusive embodiments, the MRD target is acytokine. In another nonexclusive embodiment, the MRD target is a factorthat regulates angiogenesis.

The MRDs are able to bind their respective target when the MRDs areattached to an antibody. In some embodiments, the MRD is able to bindits target when not attached to an antibody.

The sequence of the MRD can be determined several ways. For example, MRDsequences can be derived from natural ligands or known sequences thatbind to a specific target binding site. Additionally, phage displaytechnologies have emerged as a powerful method in identifying peptideswhich bind to target receptors and ligands. In peptide phage displaylibraries, naturally occurring and non-naturally occurring (e.g., randompeptide) sequences can be displayed by fusion with coat proteins offilamentous phage. The methods for elucidating binding sites onpolypeptides using phage display vectors has been previously described,in particular in WO 94/18221, which is herein incorporated by reference.The methods generally involve the use of a filamentous phage (phagemid)surface expression vector system for cloning and expressing polypeptidesthat bind to the pre-selected target site of interest.

The methods of the present invention for preparing MRDs include the useof phage display vectors for their particular advantage of providing ameans to screen a very large population of expressed display proteinsand thereby locate one or more specific clones that code for a desiredtarget binding reactivity.

Variants and derivatives of the MRDs that retain the ability to bind thetarget antigen are included within the scope of the present invention.Included within variants are insertional, deletional, and substitutionalvariants, as well as variants that include MRDs presented herein withadditional amino acids at the N- and/or C-terminus, including from about0 to 50, 0 to 40, 0 to 30, 0 to 20 amino acids and the like. It isunderstood that a particular MRD of the present invention may bemodified to contain one, two, or all three types of variants.Insertional and substitutional variants may contain natural amino acids,unconventional amino acids, or both. In some embodiments, the MRDcontains a sequence with no more than 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15,or 20 amino acid differences when compared to an MRD sequence describedherein. In some embodiments, the amino acid differences aresubstitutions. These substitutions can be conservative ornon-conservative in nature and can include unconventional or non-naturalamino acids.

The ability of an MRD to bind its target can be assessed using anytechnique that assesses molecular interaction. For example, MRD-targetinteraction can be assayed as described in the Examples below oralternatively, using in vitro or in vivo binding assays such as westernblots, radioimmunoassays, ELISA (enzyme linked immunosorbent assay),“sandwich” immunoassays, immunoprecipitation assays, fluorescentimmunoassays, protein A immunoassays, and immunohistochemistry (IHC).Assays evaluating the ability of an MRD to functionally affect it'starget (e.g., assays to measure signaling, proliferation, migrationetc.) can also be used to indirectly assess MRD-target interaction.

Once the sequence of the MRD has been elucidated, the peptides may beprepared by any of the methods known in the art. For example, the MRDpeptides can be chemically synthesized and operably attached to theantibody or can be synthesized using recombinant technology. Forexample, MRDs can be synthesized in solution or on a solid support usingknown techniques. Various automatic synthesizers are commerciallyavailable and can be used in accordance with known protocols. See, forexample, Tam et al., J. Am. Chem. Soc., 105:6442 (1983); Merrifield,Science 232:341-347 (1986); Barany and Merrifield, The Peptides, Grossand Meienhofer, eds, Academic Press, New York, 1-284; Barany et al.,Int. J. Pep. Protein Res., 30:705 739 (1987); and U.S. Pat. No.5,424,398, which are herein incorporated by reference.

The following MRD targets are described in more detail by way of exampleonly.

In some embodiments described herein, the MRD targets an integrin. Therole of integrins such as αvβ3 and αvβ5 as tumor-associated markers hasbeen well documented. A recent study of 25 permanent human cell linesestablished from advanced ovarian cancer demonstrated that all lineswere positive for αvβ5 expression and many were positive for αvβ3expression. Studies have also shown that αvβ3 and αvβ5 is highlyexpressed on malignant human cervical tumor tissues. Integrins have alsodemonstrated therapeutic effects in animal models of Kaposi's sarcoma,melanoma, and breast cancer.

A number of integrin αvβ3 and αvβ5 antagonists are in clinicaldevelopment. These include cyclic RGD peptides and synthetic smallmolecule RGD mimetics. Two antibody-based integrin antagonists arecurrently in clinical trials for the treatment of cancer. The first isVITAXIN® (MEDI-522, Abegrein), the humanized form of the murineanti-human αvβ3 antibody LM609. A dose-escalating phase I study incancer patients demonstrated that VITAXIN® is safe for use in humans.Another antibody in clinical trials is CNT095, a fully human Ab thatrecognizes αv integrins. A Phase I study of CNT095 in patients with avariety of solid tumors has shown that it is well tolerated. Cilengitide(EMD 121974), a peptide antagonist of αvβ3 and αvβ5, has also provensafe in phase I trials. Furthermore, there have been numerous drugtargeting and imaging studies based on the use of ligands for thesereceptors. These preclinical and clinical observations demonstrate theimportance of targeting αvβ3 and αvβ5 and studies involving the use ofantibodies in this strategy have consistently reported that targetingthrough these integrins is safe.

Integrin-binding MRDs containing one more RGD tripeptide sequence motifsrepresent an example of MRDs of the invention. Ligands having the RGDmotif as a minimum recognition domain and from which MRDs of theinvention can be derived are well known, a partial list of whichincludes, with the corresponding integrin target in parenthesis,fibronectin (α3β1, α5β1, αvβ1, α11bβ3, αvβ3, and α3β1) fibrinogen (αMβ2and α11bβ1) von Willebrand factor (α11bβ3 and αvβ3), and vitronectin(α11bβ3, αvβ3 and αvβ5).

In one embodiment, the RGD containing targeting MRD is a member selectedfrom the group consisting of: YCRGDCT (SEQ ID NO:3); PCRGDCL (SEQ IDNO:4); TCRGDCY (SEQ ID NO:5); and LCRGDCF (SEQ ID NO:6).

A MRD that mimics a non-RGD-dependent binding site on an integrinreceptor and having the target binding specificity of a high affinityligand that recognizes the selected integrin is also contemplated in thepresent invention. MRDs that bind to an integrin receptor and disruptbinding and/or signaling activity of the integrin are also contemplated.

In some embodiments, the MRD targets an angiogenic molecule.Angiogenesis is essential to many physiological and pathologicalprocesses. Ang2 has been shown to act as a proangiogenic molecule.Administration of Ang2-selective inhibitors is sufficient to suppressboth tumor angiogenesis and corneal angiogenesis. Therefore, Ang2inhibition alone or in combination with inhibition of other angiogenicfactors, such as VEGF, can represent an effective antiangiogenicstrategy for treating patients with solid tumors.

It is contemplated that MRDs useful in the present invention includethose that bind to angiogenic receptors, angiogenic factors, and/orAng2. In a specific embodiment, an MRD of the invention binds Ang2. Inone embodiment, the angiogenic cytokine targeting MRD sequences orMRD-containing sequences contain a sequence selected from the group:MGAQTNFMPMDDLEQRLY EQFILQQGLE (SEQ ID NO:7); MGAQTNFMPMDNDELLLYEQFILQQGLE (SEQ ID NO:8); MGAQTNFMPMDAT ETRLYEQFILQQGLE (SEQ IDNO:9); AQQEECEWDPWTCEHMGSGSATGGSGSTASSGSGSATHQEECEWDPW TCEHMLE (SEQ IDNO:10) (2xCon4); MGAQTNFMPMDNDELLNYEQFI LQQGLE (SEQ ID NO:11); andPXDNDXLLNY (SEQ ID NO:12) where X is one of the 20 naturally-occurringamino acids.

In another embodiment, the angiogenic cytokine targeting MRD sequencesor MRD-containing sequences contain a sequence selected from thegroup:MGAQTNFMPMDNDELLLYEQFILQQGLEGGSGSTASSGSGSSLGAQTNFMPMDNDELLLY (SEQID NO:20); AQQEECEWDPWTCEH MGSGSATGGSGSTASSGSGSATHQEECEWDPWTCEHMLE (SEQID NO:10); AQQEECEFAPWTCEHM (SEQ ID NO:21) (ConFA); core nEFAPWTn (SEQID NO:22) where n is from about 0 to 50 amino acid residues;AQQEECEFAPWTCEHMGSGSATGGSGSTASSGSGSATHQ EECEFAPWTCEHMLE (SEQ ID NO:23)(2xConFA); and AQQEECELAPWTCEHM (SEQ ID NO:24) (ConLA).

In another embodiment, the angiogenic cytokine targeting MRD sequencesor MRD-containing sequences contain a sequence selected from the group:

XnELAPWTXn where n is from about 0 to 50 amino acid residues and X isany amino acid (SEQ ID NO:25); AQQEECELAPWTCEHMGSGSATGGSGSTASSGSGSATHQEECELAPWTCEHMLE (SEQ ID NO:26) (2xConLA); AQQEECEFSPWTCEHM (SEQ ID NO:27) (ConFS); XnEFSPWTXn where n is from about 0 to 50amino acid residues and X is any amino acid (SEQ ID NO:28);AQQEECEFSPWTCEHMGSGSATGGSGSTASSGSGSATHQEECEFSPWT CEHMLE (SEQ ID NO:29)(2xConFS); AQQEECELEPWTCEHM (SEQ ID NO:30) (ConLE); XnELEPWTXn where nis from about 0 to 50 amino acid residues (SEQ ID NO:31) and wherein Xis any amino acid; andAQQEECELEPWTCEHMGSGSATGGSGSTASSGSGSATHQEECELEPWTCE HMLE (SEQ ID NO:32)(2xConLE).

It should be understood that such the MRDs of the invention can bepresent in tandem dimers, trimers or other multimers either homologousor heterologous in nature. For example, one can dimerize identicalCon-based sequences such as in 2xConFA to provide a homologous dimer, orthe Con peptides can be mixed such that ConFA is combined with ConFA tocreate ConFA-LA heterodimer with the sequence:AQQEECEFAPWTCEHMGSGSATGGSGSTASSGSGSATHQEECE LAPWTCEHMLE (SEQ ID NO:33).

Another heterodimer of the invention is ConFA combined with ConFS tocreate ConFA-FS with the sequence: AQQEECEFAPWTCEHMGSGSATGGSGSTASSGSGSATHQEECEFSPWTCEHMLE (SEQ ID NO:34).

One of skill in the art, given the teachings herein, will appreciatethat other such combinations will create functional Ang2 binding MRDs asdescribed herein.

The invention also includes human Ang2 MRDs having a core sequenceselected from: XnEFAPWTXn where n is from about 0 to 50 amino acidresidues (SEQ ID NO:22); XnELAPWTXn where n is from about 0 to 50 aminoacid residues (SEQ ID NO:25); XnEFSPWTXn where n is from about 0 to 50amino acid residues (SEQ ID NO:28); XnELEPWTXn where n is from about 0to 50 amino acid residues (SEQ ID NO:31); and Xn AQQEECEX₁X₂PWTCEHMXnwhere n is from about 0 to 50 amino acid residues and X represents anynatural amino acid (SEQ ID NO:57).

In some embodiments, the MRD targets vascular endothelial growth factor(VEGF). Phage display selections and structural studies of VEGFneutralizing peptides in complex with VEGF have been reported. Thesestudies have revealed that peptide vI 14 (VEPNCDIHVMWEWECFERL) (SEQ IDNO:13) is VEGF specific, binds VEGF with 0.2 μM affinity, andneutralizes VEGF-induced proliferation of Human Umbilical VeinEndothelial Cells (HUVEC). Since VEGF is a homodimer, the peptideoccupies two identical sites at either end of the VEGF homodimer. In aspecific embodiment, the antibody-MRD fusion of the invention comprisesvI14. In other embodiments, the antibody-MRD fusion comprisesvariants/derivatives that competitively inhibit the ability of theantiboby-vI14 fusion to bind to VEGF. In additional embodiments, ananti-VEGF antibody containing an MRD that targets VEGF is contemplatedin the present invention. Anti-VEGF antibodies can be found for examplein Presta et al., Cancer Research 57:4593-4599, (1997); and Fuh et al.,J Biol Chem 281:10 6625, (2006), which are herein incorporated byreference.

Insulin-like growth factor-I receptor-specific MRDs can also be used inthe present invention. In one embodiment, the MRD sequence that targetsthe insulin-like growth factor-I receptor is SFYSCLESLVNGPAEKSRGQWDGCRKK(SEQ ID NO:14).

In one aspect, the invention includes an IGF1R binding MRD having thesequence: NFYQCIXIX2LX3X4X5PAEKSRGQWQECRTGG (SEQ ID NO:58), wherein X1is E or D; X2 is any amino acid; X3 is any amino acid; X4 is any aminoacid and X5 is any amino acid.

In another embodiment, the IGF1R binding MRD contains a sequenceselected from the group: NFYQCIEMLASHPAEKSRGQWQECRTGG (SEQ ID NO:35);NFYQ CIEQLALRPAEKSRGQWQECRTGG (SEQ ID NO:36); NFYQCIDLLMAYPAEKSRGQWQECRTGG (SEQ ID NO:37); NFYQCIERLVTGPAEKSRGQWQECRTGG (SEQ ID NO:38);NFYQCIEYLAMKPAEKSRGQWQECRTGG (SEQ ID NO:39); andNFYQCIEALQSRPAEKSRGQWQECRTGG (SEQ ID NO:40).

In another embodiment, the IGF1R binding MRD contains a sequenceselected from the group: NFYQCIEALSRSPAEKSRGQWQECRTGG (SEQ ID NO:41);NFYQCIEH LSGSPAEKSRGQWQECRTG (SEQ ID NO:42); NFYQCIESLAGGPAEKSRGQWQECRTG (SEQ ID NO:43); NFYQCIEALVGVPAEKSRGQWQECRTG (SEQ ID NO:44); andNFYQCIEMLSLPPAEKSRGQWQECRTG (SEQ ID NO:45).

In another embodiment, the IGF1R binding MRD contains a sequenceselected from the group: NFYQCIEVFWGRPAEKSRGQWQECRTG (SEQ ID NO:46);NFYQCIE QLSSGPAEKSRGQWQECRTG (SEQ ID NO:47); NFYQCIELLSARPAEKSRGQWAECRAG (SEQ ID NO:48); and NFYQCIEALARTPAEKSRGQWVECRAP (SEQ ID NO:49).

Vascular homing-specific MRDs are also contemplated for use in thepresent invention. A number of studies have characterized the efficacyof linking the vascular homing peptide to other proteins like IL-12 ordrugs to direct their delivery in live animals. One example of an MRDsequence that is a vascular homing peptide that is envisioned to beincluded within an antibody-MRD fusion of the invention is ACDCRGDCFCG(SEQ ID NO:15).

Numerous other target binding sites are contemplated as being the targetof the antibody-MRD fusions of the present invention, including forexample, epidermal growth factor receptor (EGFR), CD20, tumor antigens,ErbB2, ErbB3, ErbB4, insulin-like growth factor-I receptor, nerve growthfactor (NGR), hepatocyte growth factor receptor, and tumor-associatedsurface antigen epithelial cell adhesion molecule (Ep-CAM). MRDs can bedirected towards these target binding sites.

In one embodiment, the MRD sequence that binds to EGFR and that isenvisioned to be included within an antibody-MRD fusion is selected fromthe group: VDNKFNKELEKAYNEIRNLPNLNGWQMTAFIASLVDDPSQSA NLLAEAKKLNDAQAPK(SEQ ID NO:16); and VDNKFNKEMWIAWEEIRNLPNLNGWQMTAFIASLVDDPSQSANLLAEAKKLNDAQAPK (SEQ ID NO:17).

In another embodiment, the MRD binds ErbB2 and has the sequence:VDNKFNKEMRNAYWEIALLPNLNNQQKRAFIRSLYDDPSQSANLLAEAKKLNDAQAPK (SEQ ID NO:18).

In some embodiments, the MRD binds to a human protein.

III. ANTIBODIES

The antibody in the MRD-containing antibodies described herein can beany suitable antigen-binding immunoglobulin. In certain embodiments, theMRD-containing antibody molecules described herein retain the structuraland functional properties of traditional monoclonal antibodies. Thus,the antibodies retain their epitope binding properties, butadvantageously also incorporate one or more additional target-bindingspecificities.

Antibodies that can be used in the MRD-containing antibodies include,but are not limited to, monoclonal, multispecific, human, humanized, andchimeric antibodies. Immunoglobulin or antibody molecules of theinvention can be of any type (e.g., IgG, IgE, IgM, IgD, IgA, and IgY),class (e.g., IgG1, IgG2, IgG3, IgG4, IgA1 and IgA2) or subclass ofimmunoglobulin molecule. In specific embodiments, the antibodies areIgG1. In other specific embodiments, the antibodies are IgG3.

Antibodies that can be used as part of the MRD-containing antibodies canbe naturally derived or the result of recombinant engineering (e.g.,phage display, xenomouse, and synthetic). In specific embodiments, theantibodies are human.

In certain embodiments, the heavy chain portions of one polypeptidechain of a multimer are identical to those on a second polypeptide chainof the multimer. In alternative embodiments, the heavy chainportion-containing monomers of the invention are not identical. Forexample, each monomer may comprise a different target binding site,forming, for example, a bispecific antibody.

Bispecific, bivalent antibodies, and methods of making them, aredescribed, for instance in U.S. Pat. Nos. 5,731,168; 5,807,706;5,821,333; and U.S. Appl. Publ. Nos. 2003/020734 and 2002/0155537, whichare herein incorporated by reference. Bispecific tetravalent antibodies,and methods of making them are described, for instance, in WO 02/096948and WO 00/44788, the disclosures of both of which are hereinincorporated by reference. See generally, PCT publications WO 93/17715;WO 92/08802; WO 91/00360; WO 92/05793; Tutt et al., J. Immunol.147:60-69 (1991); U.S. Pat. Nos. 4,474,893; 4,714,681; 4,925,648;5,573,920; and 5,601,819; and Kostelny et al., J. Immunol. 148:1547-1553(1992).

Affinity maturation strategies and chain shuffling strategies (see,e.g., Marks et al., Bio/Technology 10:779-783 (1992), which is hereinincorporated by reference) are known in the art and can be employed togenerate high affinity antibodies that can be used in the MRD-containingantibodies described herein.

In certain embodiments, the MRD-containing antibodies have been modifiedso as to not elicit a deleterious immune response in the animal to betreated, e.g., in a human. In one embodiment, the antibody is modifiedto reduce immunogenicity using art-recognized techniques. For example,antibody components of the MRD-containing antibodies can be humanized,deimmunized, or chimerized. These types of antibodies are derived from anon-human antibody, typically a murine antibody, that retains orsubstantially retains the antigen-binding properties of the parentantibody, but which is less immunogenic in humans. This may be achievedby various methods, including (a) grafting the entire non-human variabledomains onto human constant regions to generate chimeric antibodies; (b)grafting at least a part of one or more of the non-human complementaritydetermining regions (CDRs) into human frameworks and constant regionswith or without retention of critical framework residues; or (c)transplanting the entire non-human variable domains, but “cloaking” themwith human-like sections by replacement of surface residues. Suchmethods are disclosed in Morrison et al., Proc. Natl. Acad. Sci.81:6851-6855 (1984); Morrison et al., Adv. Immunol. 44:65-92 (1988);Verhoeyen et al., Science 239:1534-1536 (1988); Padlan, Molec. Immun.28:489-498 (1991); Padlan, Molec. Immun. 31:169-217 (1994), and U.S.Pat. Nos. 5,585,089, 5,693,761, 5,693,762, and 6,190,370, all of whichare herein incorporated by reference.

Many different antibody components of the MRD-containing antibodies canbe used in the methods described herein. It is contemplated thatcatalytic and non-catalytic antibodies can be used in the presentinvention. For example, Antibody 38C2 is an antibody-secreting hybridomaand has been previously described in WO 97/21803. 38C2 contains anantibody combining site that catalyzes the aldol addition reactionbetween an aliphatic donor and an aldehyde acceptor. In a syngeneicmouse model of neuroblastoma, systemic administration of an etoposideprodrug and intra-tumor injection of Ab 38C2 inhibited tumor growth.

The antibody target of the MRD-containing antibody (i.e., the target ofthe antigenic binding domain) can be any molecule that it is desirablefor a MRD-antibody fusion to interact with. For example, the antibodytarget can be a soluble factor or the antibody target can be atransmembrane protein, such as a cell surface receptor. The antibodytarget can also be an extracellular component. In certain nonexclusiveembodiments, the antibody target is a factor that regulates cellproliferation, differentiation, or survival. In another nonexclusiveembodiment, the antibody target is a cytokine. In another nonexclusiveembodiment, the antibody target is a factor that regulates angiogenesis.In another nonexclusive embodiment, the antibody target is a factor thatregulates cellular adhesion and/or cell-cell interaction. In certainnonexclusive embodiments, the antibody target is a cell signalingmolecule. The ability of an antibody to bind to a target and to block,increase, or interfere with the biological activity of the antibodytarget can be determined using or routinely modifying assays, bioassays,and/or animal models known in the art for evaluating such activity.

In some embodiments, the antibody target of the MRD-containing antibodyis a target that has been validated in an animal model or clinicalsetting.

In other embodiments, the antibody target of the MRD-containing antibodyis a cancer antigen.

In certain embodiments, the antibody target of the MRD-containingantibody is EGFR, ErbB2, ErbB3, ErbB4, CD20, insulin-like growthfactor-I receptor, prostate specific membrane antigen, an integrin, orcMet.

In one embodiment, the antibody in the MRD-containing antibodyspecifically binds EGFR. In a specific embodiment, the antibody isERBITUX® (IMC-C225). In one embodiment, the antibody binds to the sameepitope as ERBITUX®. In another embodiment, the antibody competitivelyinhibits binding of ERBITUX® to EGFR. In another embodiment, theantibody in the MRD-containing antibody inhibits EGFR dimerization. Inanother specific embodiment, the antibody is panitumumab (e.g.,VECTIBIX®, Amgen). In another embodiment, the antibody binds to the sameepitope panitumumab. In another embodiment, the antibody competitivelyinhibits binding of panitumumab to EGFR.

In one embodiment the MRD-containing antibody specifically binds ErbB2(Her2). In a specific embodiment, the antibody is trastuzumab (e.g.,HERCEPTIN®, Genentech/Roche). In one embodiment, the antibody binds tothe same epitope as trastuzumab. In another embodiment, the antibodycompetitively inhibits binding of trastuzumab to ErbB2.

In other embodiments, the antibody in the MRD-containing antibodyspecifically binds to ErbB2. In one embodiment, the antibody in theMRD-containing antibody is an antibody that specifically binds to thesame epitope as the anti-ErbB2 antibody trastuzumab (e.g, HERCEPTIN®,Genentech). In another embodiment, the antibody in the MRD-containingantibody is an antibody that competitively inhibits ErbB2 binding by theanti-ErbB2 antibody trastuzumab. In yet another embodiment, the antibodyin the MRD-containing antibody is the anti-ErbB2 antibody trastuzumab

In some embodiments, the antibody in the MRD-containing antibodycomprises the CDRs of the anti-ErbB2 antibody trastuzumab. The CDR, VH,and VL sequences of trastuzumab are provided in Table 1.

TABLE 1 CDR Sequence VL-CDR1 RASQDVNTAVAW (SEQ ID NO: 59) VL-CDR2SASFLYS (SEQ ID NO: 60) VL-CDR3 QQHYTTPPT (SEQ ID NO: 61) VH-CDR1GRNIKDTYIH(SEQ ID NO: 62) VH-CDR2 RIYPTNGYTRYADSVKG(SEQ ID NO: 63)VH-CDR3 WGGDGFYAMDY(SEQ ID NO: 64) VLDIQMTQSPSSLSASVGDRVTITCRASQDVNTAVAWYQQKPGKAPKLLIYSASFLYSGVPSRFSGSRSGTDFTLTISSLQPEDFATYYCQQHYTTPPTFGQGTKVEIKRT (SEQ ID NO: 65) VHEVQLVESGGGLVQPGGSLRLSCAASGFNIKDTYIHWVRQAPGKGLEWVARIYPTNGYTRYADSVKGRFTISADTSKNTAYLQMNSLRAEDTAVYYCSRWGGDGFYAMDYWGQGTLVTVSS (SEQ ID NO: 66)

In one embodiment the MRD-containing antibody specifically binds ErbB3(Her3).

In one embodiment the MRD-containing antibody specifically binds VEGFA.

In one embodiment the MRD-containing antibody specifically binds IGF1R.

In one embodiment, the antibody in the MRD-containing antibodyspecifically binds integrin.

In other specific embodiments, the antibody in the MRD-containingantibody specifically binds VEGF.

In another specific embodiment, the antibody in the MRD-containingantibody is the catalytic antibody 38C2. In another embodiment, theantibody binds to the same epitope as 38C2. In another embodiment, theantibody competitively inhibits 38C2.

Other antibodies of interest include A33 binding antibodies. Human A33antigen is a transmembrane glycoprotein of the Ig superfamily. Thefunction of the human A33 antigen in normal and malignant colon tissueis not yet known. However, several properties of the A33 antigen suggestthat it is a promising target for immunotherapy of colon cancer. Theseproperties include (i) the highly restricted expression pattern of theA33 antigen, (ii) the expression of large amounts of the A33 antigen oncolon cancer cells, (iii) the absence of secreted or shed A33 antigen,(iv) the fact that upon binding of antibody A33 to the A33 antigen,antibody A33 is internalized and sequestered in vesicles, and (v) thetargeting of antibody A33 to A33 antigen expressing colon cancer inpreliminary clinical studies. Fusion of a MRD directed toward A33 to acatalytic or non-catalytic antibody would increase the therapeuticefficacy of A33 targeting antibodies.

In some embodiments, the antibody in the MRD-containing antibody bindsto a human target protein.

The antibodies in the MRD-containing antibodies are able to bind theirrespective targets when the MRDs are attached to the antibody. Incertain embodiments, the antibody binds its target independently. Insome embodiments, the antibody is a target agonist. In otherembodiments, the antibody is a target antagonist.

It is contemplated that the antibodies used in the present invention maybe prepared by any method known in the art. For example, antibodymolecules and MRD-containing antibodies can be “recombinantly produced,”i.e., produced using recombinant DNA technology.

Monoclonal antibodies that can be used as the antibody component of theMRD-containing antibodies can be prepared using hybridoma methods, suchas those described by Kohler and Milstein, Nature 256:495 (1975). Usingthe hybridoma method, a mouse, hamster, or other appropriate hostanimal, is immunized as described above to elicit the production bylymphocytes of antibodies that will specifically bind to an immunizingantigen. Lymphocytes can also be immunized in vitro. Followingimmunization, the lymphocytes are isolated and fused with a suitablemyeloma cell line using, for example, polyethylene glycol, to formhybridoma cells that can then be selected away from unfused lymphocytesand myeloma cells. Hybridomas that produce monoclonal antibodiesdirected specifically against a chosen antigen as determined byimmunoprecipitation, immunoblotting, or by an in vitro binding assay(e.g., radioimmunoassay (RIA); enzyme-linked immunosorbent assay(ELISA)) can then be propagated either in vitro, for example, usingstandard methods (Goding, Monoclonal Antibodies: Principles andPractice, Academic Press, 1986) or in vivo, for example, as ascitestumors in an animal. The monoclonal antibodies can then be purified fromthe culture medium or ascites fluid as described for polyclonalantibodies above.

Alternatively monoclonal antibodies can also be made using recombinantDNA methods, for example, as described in U.S. Pat. No. 4,816,567. Forexample, in one approach polynucleotides encoding a monoclonal antibodyare isolated from mature B-cells or hybridoma cell, such as by RT-PCRusing oligonucleotide primers that specifically amplify the genesencoding the heavy and light chains of the antibody, and their sequenceis determined using conventional procedures. The isolatedpolynucleotides encoding the heavy and light chains are then cloned intosuitable expression vectors, which when transfected into host cells suchas E. coli cells, simian COS cells, Chinese hamster ovary (CHO) cells,or myeloma cells that do not otherwise produce immunoglobulin protein,monoclonal antibodies are generated by the host cells. In otherapproaches, recombinant monoclonal antibodies or antibody fragmentshaving the desired immunoreactivity can be isolated from phage displaylibraries expressing CDRs of the desired species using techniques knownin the art (McCafferty et al., Nature, 348:552-554 (1990); Clackson etal., Nature, 352:624-628 (1991); and Marks et al., J. Mol. Biol.,222:581-597 (1991)).

The polynucleotide(s) encoding a monoclonal antibody can further bemodified in a number of different manners, using recombinant DNAtechnology to generate alternative antibodies. For example,polynucleotide sequences that encode one or more MRDs and optionallylinkers, can be operably fused, for example, to the 5′ or 3′ end ofsequence encoding monoclonal antibody sequences. In some embodiments,the constant domains of the light and heavy chains of, for example, amouse monoclonal antibody can be substituted (1) for those regions of,for example, a human antibody to generate a chimeric antibody or (2) fora non-immunoglobulin polypeptide to generate a fusion antibody.Techniques for site-directed and high-density mutagenesis of thevariable region are known in the art and can be used to optimizespecificity, affinity, etc. of a monoclonal antibody.

In certain embodiments, the antibody of the MRD-containing antibody is ahuman antibody. For example, human antibodies can be directly preparedusing various techniques known in the art. Immortalized human Blymphocytes immunized in vitro or isolated from an immunized individualthat produce an antibody directed against a target antigen can begenerated (See, e.g., Cole et al., Monoclonal Antibodies and CancerTherapy, Alan R. Liss, p. 77 (1985); Boerner et al., J. Immunol., 147(1):86-95 (1991); and U.S. Pat. Nos. 5,750,373 and 6,787,637). In oneembodiment, the human antibody can be derived from the “minilocusapproach” in which an exogenous Ig locus is mimicked through inclusionof individual genes from the Ig locus (see e.g., U.S. Pat. No.5,545,807). Methods of preparing a human antibody from a phage library,and optionally optimizing binding affinity are known in the art anddescribed, for example, in Vaughan et al., Nat. Biotech., 14:309-314(1996); Sheets et al., Proc. Nat'l. Acad. Sci., 95:6157-6162 (1998);Hoogenboom Nat. Biotechnology 23:1105-1116 (2005); Hoogenboom andWinter, J. Mol. Biol., 227:381 (1991); Persic et al., Gene 187:9-18(1997); Jostock et al., J. Immunol. Methods 289:65-80 (2004); Marks etal., J. Mol. Biol., 222:581 (1991)); Barbas III, C. F., Kang, A. S.,Lerner, R. A. and Benkovic, S. J., Proc. Natl. Acad. Sci. USA,88:7978-7982 (1991); Barbas III, C. F., Hu, D., Dunlop, N., Sawyer, L.,Cababa, D., Hendry, R. M., Nara, P. L. and Burton, D. R., Proc. Natl.Acad. Sci. USA, 91:3809-3813 (1994); Yang, W.-P., Green, K.,Pinz-Sweeney, S., Briones, A. T., Burton, D. R., and Barbas III, C. F.,J. Mol. Biol., 254:392-403 (1995); and Barbas III, C. F., Bain, J. D.,Hoekstra, D. M. and Lerner, R. A. Proc. Natl. Acad. Sci. USA,89:4457-4461 (1992). Techniques for the generation and use of antibodyphage libraries are also described in: U.S. Pat. Nos. 5,545,807,5,969,108, 6,172,197, 5,885,793, 6,521,404, 6,544,731, 6,555,313,6,582,915, 6,593,081, 6,300,064, 6,653,068, 6,706,484, and 7,264,963;and Rothe et al., J. Mol. Bio. 130:448-54 (2007) (each of which isherein incorporated by reference). Affinity maturation strategies andchain shuffling strategies (Marks et al., Bio/Technology 10:779-783(1992) (which is herein incorporated by reference) are known in the artand can be employed to generate high affinity human antibodies.

Antibodies can also be made in mice that are transgenic for humanimmunoglobuin genes or fragments of these genes and that are capable,upon immunization, of producing a broad repertoire of human antibodiesin the absence of endogenous immunoglobulin production. This approach isdescribed in: Lonberg, Nat. Biotechnol 23:1117-1125 (2005), Green,Nature Genet. 7:13-21 (1994), and Lonberg, Nature 368:856-859 (1994);U.S. Pat. Nos. 5,545,807, 5,545,806, 5,569,825, 5,625,126, 5,633,425,5,661,016, 6,596,541, 7,105,348, and 7,368,334 (each of which is hereinincorporated by reference).

IV. LINKERS

MRD-containing antibodies can contain a single linker, multiple linkers,or no linker. Thus, a MRD may be operably attached (linked) to theantibody directly, or operably attached through an optional linkerpeptide. Similarly, a MRD may be operably attached to one or more MRD(s)directly, or operably attached to one or more MRD(s) through one or moreoptional linker peptide(s). Linkers can be of any size or composition solong as they are able to operably attach an MRD and an antibody suchthat the MRD enables the MRD containing antibody to bind the MRD target.In some embodiments, linkers have about 1 to 20 amino acids, about 1 to15 amino acids, about 1 to 10 amino acids, about 1 to 5 amino acids,about 2 to 20 amino acids, about 2 to 15 amino acids, about 2 to 10amino acids, or about 2 to 5 amino acids. The linker can also have about4 to 15 amino acids.

In certain embodiments, the linker peptide contains a short linkerpeptide with the sequence GGGS (SEQ ID NO:1), a medium linker peptidewith the sequence SSGGGGSGGGGGGSS (SEQ ID NO:2), or a long linkerpeptide with the sequence SSGGGGSGGGGGGSSRSS (SEQ ID NO:19). In anotherembodiment, the MRD is inserted into the fourth loop in the light chainconstant region.

Linker optimization can be evaluated using the techniques described inExamples 1-17 and techniques otherwise known in the art. Linkerspreferably should not disrupt the ability of an MRD and/or an antibodyto bind target molecules.

V. ANTIBODIES CONTAINING MRDS

Using the methods described herein, multi-specificity and greatermulti-valency can be achieved through the fusion of MRDs to antibodies.

The MRDs of the MRD-containing antibodies prepared according to thepresent invention, may be operably linked to an antibody through thepeptide's N-terminus or C-terminus. The MRD may be operably linked tothe antibody at the C-terminal end of the heavy chain of the antibody,the N-terminal end of the heavy chain of the antibody, the C-terminalend of the light chain of the antibody, or the N-terminal end of thelight chain of the antibody. Optimization of the MRD composition,MRD-antibody attachment location and linker composition can be performedusing the binding assays described in Examples 1-18 and bioassays andother assays known in the art for the appropriate target relatedbiological activity.

In one embodiment, MRD-containing antibodies contain an MRD operablylinked to either the antibody heavy chain, the antibody light chain, orboth the heavy and the light chain. In one embodiment an MRD-containingantibody contains at least one MRD linked to one of the antibody chainterminals. In another embodiment, an MRD-containing antibody of theinvention contains at least one MRD operably linked to two of theantibody chain terminals. In another embodiment, an MRD-containingantibody contains at least one MRD operably linked to three of theantibody chain terminals. In another embodiment, an MRD-containingantibody contains at least one MRD operably attached to each of the fourantibody chain terminals (i.e., the N and C terminals of the light chainand the N and C terminals of the heavy chain).

In certain specific embodiments, the MRD-containing antibody has atleast one MRD operably attached to the N-terminus of the light chain. Inanother specific embodiment, the MRD-containing antibody has at leastone MRD operably attached to the N-terminus of the heavy chain. Inanother specific embodiment, the MRD-containing antibody has at leastone MRD operably attached to the C-terminus of the light chain. Inanother specific embodiment, the MRD-containing antibody has at leastone MRD operably attached to the C-terminus of the heavy chain.

An MRD-containing antibody can be “multispecific” (e.g., bispecific,trispecific tetraspecific, pentaspecific or of greatermultispecificity). Thus, whether an MRD-containing antibody is“monospecific” or “multispecific,” (e.g., bispecific, trispecific, andtetraspecific) refers to the number of different epitopes that theMRD-containing antibody binds. The present invention contemplates thepreparation of mono-, bi-, tri-, tetra-, and penta-specific antibodiesas well as antibodies of greater multispecificity. In one embodiment,the MRD-containing antibody binds two different epitopes. In anadditional embodiment the MRD-containing antibody binds two differentepitopes simultaneously. In another embodiment, the MRD-containingantibody binds three different epitopes. In an additional embodiment theMRD-containing antibody binds three different epitopes simultaneously.In another embodiment, the MRD-containing antibody binds four differentepitopes. In an additional embodiment the MRD-containing antibody bindsfour different epitopes simultaneously. In another embodiment, theMRD-containing antibody binds five different epitopes (see, e.g., FIG.2D). In an additional embodiment the MRD-containing antibody binds fivedifferent epitopes simultaneously.

In other embodiments two MRDs of the MRD-containing antibody bind thesame antigen. In other embodiments three, four, five, six, seven, eight,nine or ten MRDs of the MRD-containing antibody bind the same antigen.In other embodiments at least two MRDs of the MRD-containing antibodybind the same antigen. In other embodiments at least three, four, five,six, seven, eight, nine or ten MRDs of the MRD-containing antibody bindthe same antigen.

In other embodiments, the antibody and one MRD of the MRD-containingantibody bind the same antigen. In other embodiments the antibody andtwo, three, four, five, six, seven, eight, nine or ten MRDs of theMRD-containing antibody bind the same antigen. In other embodiments, theantibody and at least one MRD of the MRD-containing antibody bind thesame antigen. In other embodiments the antibody and at least two, three,four, five, six, seven, eight, nine or ten MRDs of the MRD-containingantibody bind the same antigen.

The present invention also provides for two or more MRDs which arelinked to any terminal end of the antibody. Thus, in one non-exclusiveembodiment, two, three, four, or more MRDs are operably linked to theN-terminal of the heavy chain. In another non-exclusive embodiment, two,three, four, or more MRDs are operably linked to the N-terminal of thelight chain. In another non-exclusive embodiment, two, three, four, ormore MRDs are operably linked to the C-terminal of the heavy chain. Inanother non-exclusive embodiment, two, three, four, or more MRDs areoperably linked to the C-terminal of the light chain. It is envisionedthat these MRDs can be the same or different. In addition, anycombination of MRD number and linkages can be used. For example, twoMRDs can be operably linked to the N-terminal of the heavy chain of anantibody which contains one MRD linked to the C-terminal of the lightchain. Similarly, three MRDs can be operably linked to the C-terminal ofthe light chain and two MRDs can be operably linked to the N-terminal ofthe light chain.

MRD-containing antibodies can contain one, two, three, four, five, six,seven, eight, nine, ten or more than ten MRDs.

In one embodiment, the MRD-containing antibody contains one MRD (see,e.g., FIGS. 2B and 2C). In another embodiment, the MRD-containingantibody contains two MRDs. In another embodiment, the MRD-containingantibody contains three MRDs. In another embodiment, the MRD-containingantibody contains four MRDs (see, e.g., FIGS. 2B and 2C). In anotherembodiment, the MRD-containing antibody contains five MRDs. In anotherembodiment, the MRD-containing antibody contains six MRDs. In anadditional embodiment, the MRD-containing antibody contains between twoand ten MRDs.

In one embodiment, the MRD-containing antibody contains at least oneMRD. In another embodiment, the MRD-containing antibody contains atleast two MRDs. In another embodiment, the MRD-containing antibodycontains at least three MRDs. In another embodiment, the MRD-containingantibody contains at least four MRDs. In another embodiment, theMRD-containing antibody contains at least five MRDs. In anotherembodiment, the MRD-containing antibody contains at least six MRDs.

In another embodiment, the MRD-containing antibody contains twodifferent MRDs. In another embodiment, the MRD-containing antibodycontains three different MRDs. In another embodiment, the MRD-containingantibody contains four different MRDs. In another embodiment, theMRD-containing antibody contains five different MRDs. In anotherembodiment, the MRD-containing antibody contains six different MRDs. Inan additional embodiment, the MRD-containing antibody contains betweentwo and ten different MRDs.

In another embodiment, the MRD-containing antibody contains at least twodifferent MRDs. In another embodiment, the MRD-containing antibodycontains at least three different MRDs. In another embodiment, theMRD-containing antibody contains at least four different MRDs. Inanother embodiment, the MRD-containing antibody contains at least fivedifferent MRDs. In another embodiment, the MRD-containing antibodycontains at least six different MRDs.

Thus, the MRD-containing antibodies can be MRD monomeric (i.e.,containing one MRD at the terminus of a peptide chain optionallyconnected by a linker) or MRD multimeric (i.e., containing more than oneMRD in tandem optionally connected by a linker). The multimericMRD-containing antibodies can be homo-multimeric (i.e., containing morethan one of the same MRD in tandem optionally connected by linker(s)(e.g., homodimers, homotrimers, homotetramers etc.)) orhetero-multimeric (i.e., containing two or more MRDs in which there areat least two different MRDs optionally connected by linker(s) where allor some of the MRDs linked to a particular terminus are different (e.g.,heterodimer, heterotrimer, heterotetramer etc.)). In one embodiment, theMRD-containing antibody contains two different monomeric MRDs located atdifferent immunoglobulin termini. In another embodiment, theMRD-containing antibody contains three different monomeric MRDs locatedat different immunoglobulin termini. In another embodiment, theMRD-containing antibody contains four different monomeric MRDs locatedat different immunoglobulin termini. In another embodiment, theMRD-containing antibody contains five different monomeric MRDs locatedat different immunoglobulin termini. In another embodiment, theMRD-containing antibody contains six different monomeric MRDs located atdifferent immunoglobulin termini.

In an alternative embodiment, the MRD-containing antibody contains atleast one dimeric and one monomeric MRD located at differentimmunoglobulin termini. In another alternative embodiment, theMRD-containing antibody contains at least one homodimeric and onemonomeric MRD located at different immunoglobulin termini. In anotheralternative embodiment, the MRD-containing antibody contains at leastone heterodimeric and one monomeric MRD located at differentimmunoglobulin termini.

In an alternative embodiment, the MRD-containing antibody contains atleast one multimeric and one monomeric MRD located at differentimmunoglobulin termini. In another alternative embodiment, theMRD-containing antibody contains at least one homomultimeric and onemonomeric MRD located at different immunoglobulin termini. In anotheralternative embodiment, the MRD-containing antibody contains at leastone heteromultimeric and one monomeric MRD located at differentimmunoglobulin termini.

In an alternative embodiment, the MRD-containing antibody contains MRDsoperably linked to at least two different immunoglobulin termini. In aspecific embodiment, the MRDs fused to at least one of theimmunoglobulins is a multimer. In one embodiment, the MRDs fused to aleast one of the immunoglobulins is a homomultimer (i.e., more than oneof the same MRD operably linked in tandem, optionally linked via alinker), In another embodiment, the MRDs fused to at least one of theimmunoglobulins is a heteromultimer (i.e., two or more different MRDsoperably linked in tandem, optionally linked via a linker). In anadditional embodiment, the MRDs fused to at least one of theimmunoglobulins is a dimer. In another embodiment, the MRDs fused to aleast one of the immunoglobulins is a homodimer. In another embodiment,the MRDs fused to at least one of the immunoglobulins is a heterodimer.

The multiple MRDs can target the same target binding site, or two ormore different target binding sites.

Similarly, the antibody and the MRD in a MRD-containing antibody maybind to the same target molecule or to different target molecules.

In some embodiments, at least one MRD and the antibody in theMRD-containing antibody can bind to their targets simultaneously. In oneembodiment, each MRD in the MRD-containing antibody and the antibody canbind to its target simultaneously. Therefore, in some embodiments, theMRD-containing antibody binds two, three, four, five, six, seven, eight,nine, ten or more target molecules simultaneously.

The ability of a MRD-containing antibody to bind to multiple targetssimultaneously can be assayed using methods known in the art, including,for example, those methods described in the examples below.

In some embodiments, the MRD(s) and the antibody in the MRD-containingantibody are antagonists of their respective target molecules. In otherembodiments, the MRD(s) and the antibody in the MRD-containing antibodyare agonists of their respective target molecules. In yet otherembodiments, at least one of the MRDs in the MRD-containing antibody isan antagonist of its target molecule and the antibody is an agonist ofits target molecule. In yet another embodiment, at least one of the MRDsin the MRD-containing antibody is an agonist of its target molecule, andthe antibody is an antagonist of its target molecule.

In some embodiments, both the MRD(s) and the antibody in theMRD-containing antibody bind to soluble factors. In some embodiments,both the MRD(s) and the antibody in the MRD-containing antibody bind tocell surface molecules. In some embodiments, at least one MRD in theMRD-containing antibody binds to a cell surface molecule and theantibody in the MRD-containing antibody binds to a soluble factor. Insome embodiments, at least one MRD in the MRD-containing antibody bindsto a soluble factor and the antibody in the MRD-containing antibodybinds to a cell surface molecule.

Additional peptide sequences may be added, for example, to enhance thein vivo stability of the MRD or affinity of the MRD for its target.

In preferred embodiments, the MRD-containing antibody retains particularactivities of the parent antibody. In certain embodiments, theMRD-containing antibody is capable of inducing antibody dependent cellmediated cytotoxicity (ADCC). In additional embodiments, theMRD-containing antibody is capable of reducing tumor volume. Inadditional embodiments, the MRD-containing antibodies are capable ofinhibiting tumor growth.

In certain embodiments, the MRD-containing antibody is at least asstable as the corresponding antibody without the attached MRD. Inadditional, embodiments, the MRD-containing antibody has at least thesame affinity for Fc receptors as the corresponding parent antibody. Inother nonexclusive embodiments, the MRD-containing antibody has at leastthe same affinity for complement receptors as the corresponding parentantibody. In other nonexclusive embodiments, the MRD-containing antibodyhas at least the same half-life as the corresponding parent antibody. Inother embodiments, the MRD-containing antibody can be expressed atlevels commensurate with the corresponding parent antibody.

In specific embodiments, the MRD-containing antibody targets ErbB2 andan angiogenic factor. In specific embodiments, the MRD-containingantibody targets ErbB2 and IGF1R. In another embodiment, the antibodytargets ErbB2, and at least one MRD targets an angiogenic factor and/orIGF1R. In one embodiment, an antibody that binds to the same ErbB2epitope as trastuzumab is operably linked to at least one MRD thattargets an angiogenic factor and/or IGF1R. In an additional embodiment,an antibody that competitively inhibits trastuzumab binding is operablylinked to at least one MRD that targets an angiogenic factor and/orIGF1R. In additional embodiments, the trastuzumab antibody is operablylinked to at least one MRD that targets an angiogenic factor and/orIGF1R.

In some embodiments, an antibody that binds to ErbB2 is operably linkedto an MRD that targets Ang2. In some embodiments, the antibody thatbinds to ErbB2 is linked to an Ang2 binding MRD that binds to the sameAng2 epitope as an MRD comprising the sequence of SEQ ID NO:8. In someembodiments, the antibody that binds to ErbB2 is linked to an Ang2binding MRD that competitively inhibits an MRD comprising the sequenceof SEQ ID NO:8. In some embodiments, the antibody that binds to ErbB2 islinked to an MRD comprising the sequence of SEQ ID NO:8.

In some embodiments, at least one Ang2 binding MRD is operably linked tothe C-terminus of the heavy chain of an antibody that binds to ErbB2. Insome embodiments, at least one Ang2 binding MRD is operably linked tothe N-terminus of the heavy chain of an antibody that binds to ErbB2. Insome embodiments, at least one Ang2 binding MRD is operably linked tothe C-terminus of the light chain of an antibody that binds to ErbB2. Insome embodiments, at least one Ang2 binding MRD is operably linked tothe N-terminus of the light chain of an antibody that binds to ErbB2.

In some embodiments, at least one Ang2 binding MRD is operably linkeddirectly to an antibody that binds to ErbB2. In additional embodiments,at least one Ang2 binding MRD is operably linked to an antibody thatbinds to ErbB2 via a linker.

In some embodiments, an antibody that binds to ErbB2 is operably linkedto an MRD that targets IGF1R. In some embodiments, the antibody thatbinds to ErbB2 is linked to an IGF1R binding MRD that binds to the sameIGF1R epitope as an MRD comprising the sequence of SEQ ID NO:14. In someembodiments, the antibody that binds to ErbB2 is linked to an IGF1Rbinding MRD that competitively inhibits an MRD comprising the sequenceof SEQ ID NO:14. In some embodiments, the antibody that binds to ErbB2is linked to an MRD comprising the sequence of SEQ ID NO:14.

In some embodiments, at least one IGF1R binding MRD is operably linkedto the C-terminus of the heavy chain of an antibody that binds to ErbB2.In some embodiments, at least one IGF1R binding MRD is operably linkedto the N-terminus of the heavy chain of an antibody that binds to ErbB2.In some embodiments, at least one IGF1R binding MRD is operably linkedto the C-terminus of the light chain of an antibody that binds to ErbB2.In some embodiments, at least one IGF1R binding MRD is operably linkedto the N-terminus of the light chain of an antibody that binds to ErbB2.

In some embodiments, at least one IGF1R binding MRD is operably linkeddirectly to an antibody that binds to ErbB2. In additional embodiments,at least one IGF1R binding MRD is operably linked to an antibody thatbinds to ErbB2 via a linker.

In some embodiments, the MRD-containing antibody targets ErbB2, Ang2,and IGF1R. In some embodiments, the MRD-containing antibody comprises anantibody that targets ErbB2, an MRD that targets Ang2, and an MRD thattargets IGF1R. In some embodiments, the Ang2 and IGF1R MRDs are attachedto the same location on the anti-ErbB2 antibody. In some embodiments,the Ang2 and IGF1R MRDs are attached to different locations on theanti-ErbB2 antibody. In some embodiments, the Ang2 and IGF1R MRDs are onthe light chain of the anti-ErbB2 antibody. In some embodiments, theAng2 and IGF1R MRDs are on the heavy chain of the anti-ErbB2 antibody.In some embodiments, the Ang2 MRD is on the light chain of the ErbB2antibody, and the IGF1R MRD is on the heavy chain of the anti-ErbB2antibody. In some embodiments, the Ang2 MRD is on the heavy chain of theErbB2 antibody, and the IGF1R MRD is on the light chain of theanti-ErbB2 antibody. In some embodiments, the Ang2 MRD is on theN-terminus of the heavy chain of the ErbB2 antibody, and the IGF1R MRDis on the C-terminus of the light chain of the anti-ErbB2 antibody. Insome embodiments, the IGF1R MRD is on the N-terminus of the heavy chainof the ErbB2 antibody, and the Ang2 MRD is on the C-terminus of thelight chain of the anti-ErbB2 antibody.

In some embodiments, the anti-ErbB2 antibody operably linked to an Ang2binding MRD binds to both ErbB2 and Ang2 simultaneously. In someembodiments, the anti-ErbB2 antibody operably linked to an IGF1R bindingMRD binds to both ErbB2 and IGF1R simultaneously. In some embodiments,the anti-ErbB2 antibody operably linked to an Ang2 MRD and an IGF1R MRDbinds to ErbB2, Ang2, and IGF1R simultaneously. In some embodiments, theanti-ErbB2 antibody operably linked to an Ang2 and/or IGF1R bindingMRD(s) exhibits ADCC activity. In additional embodiments, the anti-ErbB2antibody operably linked to an Ang2 and/or IGF1R binding MRD(s)down-regulates Akt signaling. In additional embodiments, the anti-ErbB2antibody operably linked to an Ang2 binding MRD inhibits Ang2 binding toTie2. In additional embodiments, the anti-ErbB2 antibody operably linkedto an Ang2 and/or IGF1R binding MRD(s) down-regulates IGF1R signaling.In additional embodiments, the anti-ErbB2 antibody operably linked to anAng2 and/or IGF1R binding MRD(s) inhibits cell proliferation. Inadditional embodiments, the anti-ErbB2 antibody operably linked to anAng2 and/or IGF1R binding MRD(s) inhibits tumor growth.

In specific embodiments, the MRD-containing antibody targets VEGF and anangiogenic factor. In specific embodiments, the MRD-containing antibodytargets VEGF and IGF1R. In another embodiment, the antibody targetsVEGF, and at least one MRD targets an angiogenic factor and/or IGF1R.

In some embodiments, an antibody that binds to VEGF is operably linkedto an MRD that targets Ang2. In some embodiments, the antibody thatbinds to VEGF is linked to an Ang2 binding MRD that binds to the sameAng2 epitope as an MRD comprising the sequence of SEQ ID NO:8. In someembodiments, the antibody that binds to VEGF is linked to an Ang2binding MRD that competitively inhibits an MRD comprising the sequenceof SEQ ID NO:8. In some embodiments, the antibody that binds to VEGF islinked to an MRD comprising the sequence of SEQ ID NO:8.

In some embodiments, at least one Ang2 binding MRD is operably linked tothe C-terminus of the heavy chain of an antibody that binds to VEGF. Insome embodiments, at least one Ang2 binding MRD is operably linked tothe N-terminus of the heavy chain of an antibody that binds to VEGF. Insome embodiments, at least one Ang2 binding MRD is operably linked tothe C-terminus of the light chain of an antibody that binds to VEGF. Insome embodiments, at least one Ang2 binding MRD is operably linked tothe N-terminus of the light chain of an antibody that binds to VEGF.

In some embodiments, at least one Ang2 binding MRD is operably linkeddirectly to an antibody that binds to VEGF. In additional embodiments,at least one Ang2 binding MRD is operably linked to an antibody thatbinds to VEGF via a linker.

In some embodiments, an antibody that binds to VEGF is operably linkedto an MRD that targets IGF1R. In some embodiments, the antibody thatbinds to VEGF is linked to an IGF1R binding MRD that binds to the sameIGF1R epitope as an MRD comprising the sequence of SEQ ID NO:14. In someembodiments, the antibody that binds to VEGF is linked to an IGF1Rbinding MRD that competitively inhibits an MRD comprising the sequenceof SEQ ID NO:14. In some embodiments, the antibody that binds to VEGF islinked to an MRD comprising the sequence of SEQ ID NO:14.

In some embodiments, at least one IGF1R binding MRD is operably linkedto the C-terminus of the heavy chain of an antibody that binds to VEGF.In some embodiments, at least one IGF1R binding MRD is operably linkedto the N-terminus of the heavy chain of an antibody that binds to VEGF.In some embodiments, at least one IGF1R binding MRD is operably linkedto the C-terminus of the light chain of an antibody that binds to VEGF.In some embodiments, at least one IGF1R binding MRD is operably linkedto the N-terminus of the light chain of an antibody that binds to VEGF.

In some embodiments, at least one IGF1R binding MRD is operably linkeddirectly to an antibody that binds to VEGF. In additional embodiments,at least one IGF1R binding MRD is operably linked to an antibody thatbinds to VEGF via a linker.

In some embodiments, the MRD-containing antibody targets VEGF, Ang2, andIGF1R. In some embodiments, the MRD-containing antibody comprises anantibody that targets VEGF, an MRD that targets Ang2, and an MRD thattargets IGF1R. In some embodiments, the Ang2 and IGF1R MRDs are attachedto the same location on the anti-VEGF antibody. In some embodiments, theAng2 and IGF1R MRDs are attached to different locations on the anti-VEGFantibody. In some embodiments, the Ang2 and IGF1R MRDs are on the lightchain of the anti-VEGF antibody. In some embodiments, the Ang2 and IGF1RMRDs are on the heavy chain of the anti-VEGF antibody. In someembodiments, the Ang2 MRD is on the light chain of the anti-VEGFantibody, and the IGF1R MRD is on the heavy chain of the anti-VEGFantibody. In some embodiments, the Ang2 MRD is on the heavy chain of theanti-VEGF antibody, and the IGF1R MRD is on the light chain of theanti-VEGF antibody. In some embodiments, the Ang2 MRD is on theN-terminus of the heavy chain of the anti-VEGF antibody, and the IGF1RMRD is on the C-terminus of the light chain of the anti-VEGF antibody.In some embodiments, the IGF1R MRD is on the N-terminus of the heavychain of the anti-VEGF antibody, and the Ang2 MRD is on the C-terminusof the light chain of the anti-VEGF antibody.

In some embodiments, the anti-VEGF antibody operably linked to an Ang2binding MRD binds to both anti-VEGF and Ang2 simultaneously. In someembodiments, the anti-VEGF antibody operably linked to an IGF1R bindingMRD binds to both anti-VEGF and IGFR1 simultaneously. In someembodiments, the anti-VEGF antibody operably linked to an Ang2 bindingMRD and an IGF1R binding MRD binds to VEGF, Ang2, and IGF1Rsimultaneously. In some embodiments, the anti-VEGF antibody operablylinked to an Ang2 and/or IGF1R binding MRD(s) exhibits ADCC activity. Inadditional embodiments, the anti-VEGF antibody operably linked to anAng2 and/or IGF1R binding MRD(s) down-regulates VEGF signaling. Inadditional embodiments, the anti-VEGF antibody operably linked to anAng2 binding MRD inhibits Ang2 binding to Tie2. In additionalembodiments, the anti-VEGF antibody operably linked to an IGF1R bindingMRD inhibits IGF1R signaling. In additional embodiments, the anti-VEGFantibody operably linked to an Ang2 and/or IGF1R binding MRD(s) inhibitscell proliferation. In additional embodiments, the anti-VEGF antibodyoperably linked to an Ang2 and/or IGF1R binding MRD(s) inhibits tumorgrowth.

An additional advantage of MRD-containing antibodies is that they can beproduced using protocols that are known in the art for producingantibodies. The antibody-MRD fusion molecules can be encoded by apolynucleotide comprising a nucleotide sequence. Thus, thepolynucleotides described herein can encode an MRD, an antibody heavychain, an antibody light chain, a fusion protein comprising an antibodyheavy chain and at least one MRD, and/or a fusion protein comprising anantibody light chain and at least one MRD.

The antibody-MRD fusion molecules can be encoded by a polynucleoticecomprising a nucleotide sequence. A vector can contain thepolynucleotide sequence. The polynucleotide sequence can also be linkedwith a regulatory sequence that controls expression of thepolynucleotide in a host cell. A host cell, or its progeny, can containthe polynucleotide encoding the antibody-MRD fusion molecule.

VI. USES OF ANTIBODY-MRD FUSIONS

The MRD-containing antibodies described herein are useful in a varietyof applications including, but not limited to, therapeutic treatmentmethods, such as the treatment of cancer. In certain embodiments, theMRD-containing antibodies are useful for inhibiting tumor growth,reducing neovascularization, reducing angiogenesis, inducingdifferentiation, reducing tumor volume, and/or reducing thetumorigenicity of a tumor. The methods of use may be in vitro, ex vivo,or in vivo methods.

In one embodiment, the MRD-containing antibodies are useful fordetecting the presence of a factor or multiple factors (e.g., antigensor organisms) in a biological sample. The term “detecting” as usedherein encompasses quantitative or qualitative detection. In certainembodiments, a biological sample comprises a cell or tissue. In certainembodiments, such tissues include normal and/or cancerous tissues.

The present invention contemplates therapeutic compositions useful forpracticing the therapeutic methods described herein. In one embodiment,therapeutic compositions of the present invention contain aphysiologically tolerable carrier together with at least one species ofantibody comprising an MRD as described herein, dissolved or dispersedtherein as an active ingredient. In another embodiment, therapeuticcompositions of the present invention contain a physiologicallytolerable carrier together with at least one species of an MRD asdescribed herein, dissolved or dispersed therein as an activeingredient. In a preferred embodiment, the therapeutic composition isnot immunogenic when administered to a human patient for therapeuticpurposes.

The preparation of a pharmacological composition that contains activeingredients dissolved or dispersed therein is well understood in theart. Typically such compositions are prepared as sterile injectableseither as liquid solutions or suspensions, aqueous or nonaqueous.However, solid forms suitable for solution, or suspensions, in liquidprior to use can also be prepared. The preparation can also beemulsified. Thus, an antibody—MRD containing composition can take theform of solutions, suspensions, tablets, capsules, sustained releaseformulations or powders, or other compositional forms.

The active ingredient can be mixed with excipients which arepharmaceutically acceptable and compatible with the active ingredientand in amounts suitable for use in the therapeutic methods describedherein. Suitable excipients are, for example, water, saline, dextrose,glycerol, ethanol or the like and combinations thereof. In addition, ifdesired, the composition can contain minor amounts of auxiliarysubstances such as wetting or emulsifying agents, pH buffering agentsand the like which enhance the effectiveness of the active ingredient.

The therapeutic composition of the present invention can includepharmaceutically acceptable salts of the components therein.Pharmaceutically acceptable salts include the acid addition salts(formed with the free amino groups of the polypeptide) that are formedwith inorganic acids such as, for example, hydrochloric or phosphoricacids, or such organic acids as acetic, tartaric, mandelic and the like.Salts formed with the free carboxyl groups can also be derived frominorganic bases such as, for example, sodium, potassium, ammonium,calcium or ferric hydroxides, and such organic bases as isopropylamine,trimethylamine, 2-ethylamino ethanol, histidine, procaine and the like.

Physiologically tolerable carriers are well known in the art. Exemplaryof liquid carriers are sterile aqueous solutions that contain nomaterials in addition to the active ingredients and water, or contain abuffer such as sodium phosphate at physiological pH value, physiologicalsaline or both, such as phosphate-buffered saline. Still further,aqueous carriers can contain more than one buffer salt, as well as saltssuch as sodium and potassium chlorides, dextrose, propylene glycol,polyethylene glycol, and other solutes.

Liquid compositions can also contain liquid phases in addition to and tothe exclusion of water.

Exemplary of such additional liquid phases are glycerin, vegetable oilssuch as cottonseed oil, organic esters such as ethyl oleate, andwater-oil emulsions.

In one embodiment, a therapeutic composition contains an antibodycomprising a MRD of the present invention, typically in an amount of atleast 0.1 weight percent of antibody per weight of total therapeuticcomposition. A weight percent is a ratio by weight of antibody totalcomposition. Thus, for example, 0.1 weight percent is 0.1 grams ofantibody-MRD per 100 grams of total composition.

An antibody-containing therapeutic composition typically contains about10 micrograms (μg) per milliliter (ml) to about 100 milligrams (mg) perml of antibody as active ingredient per volume of composition, and morepreferably contains about 1 mg/ml to about 10 mg/ml (i.e., about 0.1 to1 weight percent).

A therapeutic composition in another embodiment contains a polypeptideof the present invention, typically in an amount of at least 0.1 weightpercent of polypeptide per weight of total therapeutic composition. Aweight percent is a ratio by weight of polypeptide total composition.Thus, for example, 0.1 weight percent is 0.1 grams of polypeptide per100 grams of total composition.

Preferably, a polypeptide-containing therapeutic composition typicallycontains about 10 micrograms (ug) per milliliter (ml) to about 100milligrams (mg) per ml of polypeptide as active ingredient per volume ofcomposition, and more preferably contains about 1 mg/ml to about 10mg/ml (i.e., about 0.1 to 1 weight percent).

In view of the benefit of using human, humanized or chimeric antibodiesin vivo in human patients, the presently described antibody-MRDmolecules are particularly well suited for in vivo use as a therapeuticreagent. The method comprises administering to the patient atherapeutically effective amount of a physiologically tolerablecomposition containing an antibody-MRD molecule of the invention.

The dosage ranges for the administration of the antibody-MRD molecule ofthe invention are those large enough to produce the desired effect inwhich the disease symptoms mediated by the target molecule areameliorated. The dosage should not be so large as to cause adverse sideeffects, such as hyperviscosity syndromes, pulmonary edema, congestiveheart failure, and the like. Generally, the dosage will vary with theage, condition, sex and extent of the disease in the patient and can bedetermined by one of skill in the art. The dosage can be adjusted by theindividual physician in the event of any complication.

A therapeutically effective amount of an antibody-MRD molecule of theinvention is typically an amount of antibody such that when administeredin a physiologically tolerable composition is sufficient to achieve aplasma concentration of from about 0.1 microgram (μg) per milliliter(ml) to about 100 μg/ml, preferably from about 1μg/ml to about 5 μg/ml,and usually about 5 μg/ml. Stated differently, the dosage can vary fromabout 0.1 mg/kg to about 300 mg/kg, preferably from about 0.2 mg/kg toabout 200 mg/kg, most preferably from about 0.5 mg/kg to about 20 mg/kg,in one or more dose administrations daily, for one or several days.

The antibody-MRD molecule of the invention can be administeredparenterally by injection or by gradual infusion over time. Although thetarget molecule can typically be accessed in the body by systemicadministration and therefore most often treated by intravenousadministration of therapeutic compositions, other tissues and deliverymeans are contemplated where there is a likelihood that the tissuetargeted contains the target molecule. Thus, antibody-MRD molecules ofthe invention can be administered intravenously, intraperitoneally,intramuscularly, subcutaneously, intracavity, transdermally, and can bedelivered by peristaltic means. MRD-containing antibodies can also bedelivered by aerosol to airways and lungs.

The therapeutic compositions containing an antibody-MRD molecule of thisinvention are conventionally administered intravenously, as by injectionof a unit dose, for example. The term “unit dose” when used in referenceto a therapeutic composition of the present invention refers tophysically discrete units suitable as unitary dosage for the subject,each unit containing a predetermined quantity of active materialcalculated to produce the desired therapeutic effect in association withthe required diluent; i.e., carrier, or vehicle. In a specificembodiment, the therapeutic compositions containing a human monoclonalantibody or a polypeptide are administered subcutaneously.

The compositions of the invention are administered in a mannercompatible with the dosage formulation, and in a therapeuticallyeffective amount. The quantity to be administered depends on the subjectto be treated, capacity of the subject's system to utilize the activeingredient, and degree of therapeutic effect desired. Precise amounts ofactive ingredient required to be administered depend on the judgment ofthe practitioner and are peculiar to each individual. However, suitabledosage ranges for systemic application are disclosed herein and dependon the route of administration. Suitable regimes for administration arealso variable, but are typified by an initial administration followed byrepeated doses at one or more hour intervals by a subsequent injectionor other administration. Alternatively, continuous intravenous infusionsufficient to maintain concentrations in the blood in the rangesspecified for in vivo therapies are contemplated.

In other embodiments, the invention provides a method for treating orpreventing a disease, disorder, or injury comprising administering atherapeutically effective amount or prophylactically effective amount ofantibody-MRD molecule to a subject in need thereof. In some embodiments,the disease, disorder or injury is cancer.

MRD-containing antibodies are expected to have at least the sametherapeutic efficacy as the antibody contained in the MRD antibodycontaining antibody when administered alone. Accordingly, it isenvisioned that the MRD-containing antibodies can be administered totreat or prevent a disease, disorder, or injury for which the antibodycontained in the MRD antibody, or an antibody that functions in the sameway as the antibody contained in the MRD antibody, demonstrates areasonably correlated beneficial activity in treating or preventing suchdisease, disorder or injury. This beneficial activity can bedemonstrated in vitro, in an in vivo animal model, or in human clinicaltrials. In one embodiment, an MRD-containing antibody is administered totreat or prevent a disease, disorder or injury for which the antibodycomponent of the MRD-containing antibody, or an antibody that functionsin the same way as the antibody contained in the MRD antibody,demonstrates therapeutic or prophylactic efficacy in vitro or in ananimal model. In another embodiment, an MRD-containing antibody isadministered to treat or prevent a disease, disorder or injury for whichthe antibody component of the MRD-containing antibody, or an antibodythat functions in the same way as the antibody contained in the MRDantibody, demonstrates therapeutic or prophylactic efficacy in humans.In another embodiment, an MRD-containing antibody is administered totreat or prevent a disease, disorder or injury for which the antibodycomponent of the MRD-containing antibody, or an antibody that functionsin the same way as the antibody contained in the MRD antibody, has beenapproved by a regulatory authority for use in such treatment orprevention.

In another embodiment, an MRD-containing antibody is administered incombination with another therapeutic to treat or prevent a disease,disorder or injury for which the antibody component of theMRD-containing antibody, or an antibody that functions in the same wayas the antibody contained in the MRD antibody, in combination with thetherapeutic, or a different therapeutic that functions in the same wayas the therapeutic in the combination, demonstrates therapeutic orprophylactic efficacy in vitro or in an animal model. In anotherembodiment, an MRD-containing antibody is administered in combinationwith another therapeutic to treat or prevent a disease, disorder orinjury for which the antibody component of the MRD-containing antibody,or an antibody that functions in the same way as the antibody containedin the MRD antibody, in combination with the therapeutic, or a differenttherapeutic that functions in the same way as the therapeutic in thecombination, demonstrates therapeutic or prophylactic efficacy inhumans. In another embodiment, an MRD-containing antibody, isadministered in combination with another therapeutic to treat or preventa disease, disorder or injury for which the antibody component of theMRD-containing antibody, or an antibody that functions in the same wayas the antibody contained in the MRD antibody, in combination with thetherapeutic, or a different therapeutic that functions in the same wayas the therapeutic in the combination, has been approved by a regulatoryauthority for use in such treatment or prevention.

In one embodiment, the invention provides a method of treating cancercomprising administering a therapeutically effective amount of a VEGFAor VEGFR binding MRD-containing antibody to a patient in need thereof.Combination therapy and compositions including MRD-containing antibodiesof the invention and another therapeutic are also encompassed by theinvention, as are methods of treatment using these compositions. Inother embodiments, compositions of the invention are administered aloneor in combination with one or more additional therapeutic agents.Combinations may be administered either concomitantly, e.g., as anadmixture, separately but simultaneously or concurrently; orsequentially. This includes presentations in which the combined agentsare administered together as a therapeutic mixture, and also proceduresin which the combined agents are administered separately butsimultaneously, e.g., as through separate intravenous lines into thesame individual. Administration “in combination” further includes theseparate administration of one of the therapeutic compounds or agentsgiven first, followed by the second.

In one embodiment, MRD-containing antibodies are administered to apatient in combination with a chemotherapy agent. In one embodiment,MRD-containing antibodies and a platinum-based therapeutic agent areadministered in combination to a patient. In additional embodiments,MRD-containing antibodies are administered to a patient in combinationwith irinotecan, fluoropyrimidine-, oxaliplatin-, and/or irinotecan. Infurther embodiments, MRD-containing antibodies are administered to apatient in combination with radiation therapy.

In another embodiment, the invention provides a method of treatingmacular degeneration comprising administering a therapeuticallyeffective amount of a VEGFA or VEGFR binding MRD-containing antibody toa patient in need thereof.

In another embodiment, the invention provides a method of treatingcancer comprising administering a therapeutically effective amount of aErbB2(HER2) binding MRD-containing antibody to a patient in needthereof. In a specific embodiment, the invention provides a method oftreating cancer comprising administering a therapeutically effectiveamount of trastuzumab comprising at least one MRD to a patient in needthereof. In one embodiment, the invention provides a method of treatingbreast cancer by administering a therapeutically effective amount oftrastuzumab comprising at least one MRD to a patient having breastcancer. In other embodiments, therapeutic effective amounts oftrastuzumab comprising at least one MRD are administered to treat apatient having metastatic breast cancer.

In another embodiment, the invention provides a method of treatingcancer comprising administering a therapeutically effective amount of aCD20-binding MRD-containing antibody to a patient in need thereof.

In another embodiment, the invention provides a method of treatingcancer comprising administering a therapeutically effective amount of aEGFR-binding MRD-containing antibody to a patient in need thereof. In aspecific embodiment, the invention provides a method of treating cancercomprising administering a therapeutically effective amount of cetuximabcomprising at least one MRD to a patient in need thereof. In oneembodiment, the invention provides a method of treating cancer byadministering a therapeutically effective amount of cetuximab comprisingat least one MRD to a patient having colorectal cancer. In anotherembodiment, therapeutic effective amounts of cetuximab comprising atleast one MRD are administered to treat a patient having metastaticcolorectal cancer, metastatic breast cancer, metastatic pancreaticcancer, or metastatic non-small cell lung carcinoma. In one embodiment,the invention provides a method of treating cancer by administering atherapeutically effective amount of cetuximab comprising at least oneMRD to a patient having squamous cell carcinoma of the head and neck.

In another embodiment, a therapeutically effective amount of anMRD-containing antibody is administered in combination with irinotecan,FOLFIRI, platinum-based chemotherapy, or radiation therapy.

In another embodiment, a therapeutically effective amount of anEGFR-binding MRD-containing antibody is administered in combination withirinotecan, FOLFIRI, platinum-based chemotherapy, or radiation therapy.In a specific embodiment, a therapeutically effective amount ofcetuximab comprising at least one MRD is administered in combinationwith irinotecan, FOLFIRI, platinum-based chemotherapy, or radiationtherapy

In some embodiments, the MRD-containing antibodies described herein areuseful for treating cancer. Thus, in some embodiments, the inventionprovides methods of treating cancer comprise administering atherapeutically effective amount of a MRD-containing antibody to asubject (e.g., a subject in need of treatment). In certain embodiments,the cancer is a cancer selected from the group consisting of colorectalcancer, lung cancer, ovarian cancer, liver cancer, breast cancer, braincancer, kidney cancer, prostate cancer, melanoma, cervical cancer, andhead and neck cancer. In certain embodiments, the cancer is breastcancer. In certain embodiments, the subject is a human.

In further embodiments, the MRD-containing antibodies described hereinare useful for treating a cancer selected from the group consisting ofcarcinoma, lymphoma, blastoma, medulloblastoma, retinoblastoma, sarcoma,liposarcoma, synovial cell sarcoma, neuroendocrine tumor, carcinoidtumor, gastrinoma, islet cell cancer, mesothelioma, schwannoma, acousticneuroma, meningioma, adenocarcinoma, melanoma, leukemia, lymphoidmalignancy, squamous cell cancer, epithelial squamous cell cancer, lungcancer, small-cell lung cancer, non-small cell lung cancer,adenocarcinoma of the lung, squamous carcinoma of the lung, cancer ofthe peritoneum, hepatocellular cancer, gastric or stomach cancer,gastrointestinal cancer, pancreatic cancer, glioblastoma, cervicalcancer, ovarian cancer, liver cancer, bladder cancer, hepatoma, coloncancer, rectal cancer, colorectal cancer, endometrial or uterinecarcinoma, salivary gland carcinoma, kidney or renal cancer, prostatecancer, vulval cancer, thyroid cancer, hepatic carcinoma, analcarcinoma, penile carcinoma, testicular cancer, esophagael cancer, atumor of the biliary tract, and head and neck cancer.

In some embodiments, MRD-containing antibodies are useful for inhibitingtumor growth. In certain embodiments, the method of inhibiting the tumorgrowth comprises contacting the cell with a MRD-containing antibody invitro. For example, an immortalized cell line or a cancer cell line thatexpresses an MRD target and/or an antibody target is cultured in mediumto which is added the MRD-containing antibody to inhibit tumor growth.In some embodiments, tumor cells are isolated from a patient sample suchas, for example, a tissue biopsy, pleural effusion, or blood sample andcultured in medium to which is added a MRD-containing antibody toinhibit tumor growth.

In some embodiments, the method of inhibiting tumor growth comprisescontacting the tumor or tumor cells with a therapeutically effectiveamount of the MRD-containing antibody in vivo. In certain embodiments,contacting a tumor or tumor cell is undertaken in an animal model. Forexample, MRD-containing antibodies can be administered to xenografts inimmunocompromised mice (e.g., NOD/SCID mice) to inhibit tumor growth. Insome embodiments, cancer stem cells are isolated from a patient samplesuch as, for example, a tissue biopsy, pleural effusion, or blood sampleand injected into immunocompromised mice that are then administered aMRD-containing antibody to inhibit tumor cell growth. In someembodiments, the MRD-containing antibody is administered at the sametime or shortly after introduction of tumorigenic cells into the animalto prevent tumor growth. In some embodiments, the MRD-containingantibody is administered as a therapeutic after the tumorigenic cellshave grown to a specified size.

In certain embodiments, the method of inhibiting tumor growth comprisesadministering to a subject a therapeutically effective amount of aMRD-containing antibody. In certain embodiments, the subject is a human.In certain embodiments, the subject has a tumor or has had a tumorremoved. In certain embodiments, the tumor expresses an antibody target.In certain embodiments, the tumor overexpresses the MRD target and/orthe antibody target.

In certain embodiments, the inhibited tumor growth is selected from thegroup consisting of brain tumor, colorectal tumor, lung tumor, ovariantumor, liver tumor, breast tumor, kidney tumor, prostate tumor,melanoma, cervical tumor, and head and neck tumor. In certainembodiments, the tumor is a breast tumor.

In additional embodiments, MRD-containing antibodies are useful forreducing tumorigenicity. Thus, in some embodiments, the method ofreducing the tumorigenicity of a tumor in a subject, comprisesadministering a therapeutically effective amount of a MRD-containingantibody to the subject. In certain embodiments, the tumor comprisescancer stem cells. In certain embodiments, the frequency of cancer stemcells in the tumor is reduced by administration of the agent.

The following examples are intended to illustrate but not limit theinvention.

EXAMPLES Example 1 Integrin Targeting Antibody-MRD Molecules

Novel antibody-MRD fusion molecules were prepared by fusion of anintegrin αvβ3-targeting peptides to catalytic antibody 38C2. Fusions atthe N-termini and C-termini of the light chain and the C-termini of theheavy chain were most effective. Using flow cytometry, the antibodyconjugates were shown to bind efficiently to integrin αvβ3-expressinghuman breast cancer cells. The antibody conjugates also retained theretro-aldol activity of their parental catalytic antibody 38C2, asmeasured by methodol and doxorubicin prodrug activation. Thisdemonstrates that cell targeting and catalytic antibody capability canbe efficiently combined for selective chemotherapy.

Example 2 Angiogenic Cytokine Targeting Antibody-MRD Molecules

Angiogenic cytokine targeting antibody-MRD fusion molecules wereconstructed. The antibody used was 38C2, which was fused with a MRDcontaining the 2xCon4 peptide(AQQEECEWDPWTCEHMGSGSATGGSGSTASSGSGSATHQEECEWDP WTCEHMLE (SEQ IDNO:10)). The MRD-containing peptide was fused to either the N- orC-terminus of the light chain and the C-terminus of the heavy chain.Similar results were found with the other Ang2 MRD peptides. AdditionalAng2 MRD peptides include:MGAQTNFMPMDNDELLLYEQFILQQGLEGGSGSTASSGSGSSLGAQTNFMPMDNDELLLY (SEQ IDNO:20) (LM-2x-32); AQQEECEWDPWTCEHMGSGSATGGSGSTASSGSGSATHQEECEWDPWTCEHMLE (SEQ ID NO:10) (2xCon4);AQQEECEFAPWTCEHM (SEQ ID NO:21) ConFA; core XnEFAPWTXn where n is fromabout 0 to 50 amino acid residues (SEQ ID NO:22);AQQEECEFAPWTCEHMGSGSATGGSGSTASSGSGSATHQEECE FAPWTCEHMLE (SEQ ID NO:23)(2xConFA); AQQEECELAPWTCEHM (SEQ ID NO:24) (ConLA); XnELAPWTXn where nis from about 0 to 50 amino acid residues (SEQ ID NO:25);AQQEECELAPWTCEHMGSGSATGGSGSTASS GSGSATHQEECELAPWTCEHMLE (SEQ ID NO:26)(2xConLA); AQQEE CEFSPWTCEHM ConFS (SEQ ID NO:27); XnEFSPWTXn where n isfrom about 0 to 50 amino acid residues (SEQ ID NO:28);AQQEECEFSPWTCEHMGSGS ATGGSGSTASSGSGSATHQEECEFSPWTCEHMLE (SEQ ID NO:29)(2xConFS); AQQEECELEPWTCEHM ConLE (SEQ ID NO:30); XnELEPWTXn where n isfrom about 0 to 50 amino acid residues (SEQ ID NO:31); andAQQEECELEPWTCEHMGSGSATGGSGSTASSGSGSATHQEECELEP WTCEHMLE (SEQ ID NO:32)(2xConLE).

It should be understood that such peptides can be present in dimmers,trimers or other multimers either homologous or heterologous in nature.For example, one can dimerize identical Con-based sequences such as in2xConFA to provide a homologous dimer, or the Con peptides can be mixedsuch that ConFA is combined with ConLA to create ConFA-LA heterodimerwith the sequence:AQQEECEFAPWTCEHMGSGSATGGSGSTASSGSGSATHQEECELAPWTCEHMLE (SEQ ID NO:33).

Another illustrative heterodimer is ConFA combined with ConFS to createConFA-FS with the sequence: AQQEECEFAPWTCEHMGSGSATGGSGSTASSGSGSATHQEECEFSPWTCEHMLE (SEQ ID NO:34).

One of skill in the art, given the teachings herein, will appreciatethat other such combinations will create functional Ang2 binding MRDs asdescribed herein.

Example 3 Antibody-MRD Fusions with Non-Catalytic Antibodies

A humanized mouse monoclonal antibody, LM609, directed towards humanintegrin αvβ3 has been previously described (Rader, C. et. al., PNAS95:8910-5 (1998)).

A human non-catalytic monoclonal Ab, JC7U was fused to an anti-Ang2 MRDcontaining 2xCon4 (AQQEECEWDPWTCEHMGSGSATGGSGSTASSGSGSATHQEECEWDPWTCEHMLE (SEQ ID NO:10)) at either the N- or C-terminus ofthe light chain. 2xCon4 (AQQEECEWDPWTCEHMGSGSATGGSGSTASSGSGSATHQEECEWDPWTCEHMLE (SEQ ID NO:10)) was studied as anN-terminal fusion to the Kappa chain of the antibody (2xCon4-JC7U) andas a C-terminal fusion (JC7U-2xCon4). Both fusions maintained integrinand Ang2 binding. As shown in the left panel of FIG. 3, both antibodyconstructs (2xCon4-JC7U and JC7U-2xCon4) specifically bound torecombinant Ang2 as demonstrated by ELISA studies. Binding to Ang2,however, is significantly higher with JC7U-2xCon4, which has the 2xCon4(SEQ ID NO:10) fusion at the C-terminus of the light chain of theantibody. The right panel of FIG. 3 depicts the binding of Ang2-JC7U andJC7U-Ang2 to integrin αvβ3. The results show that fusion of 2xCon4 (SEQID NO:10) to either the N- or the C-light chain terminus does not affectmAb JC7U binding to integrin αvβ3. FIG. 4 depicts another ELISA studyusing the same antibody-MRD fusion constructs.

Example 4 HERCEPTIN®-MRD Fusion Molecules

Another example of MRD fusions to a non-catalytic antibody areHERCEPTIN®-MRD fusion constructs. The HERCEPTIN®-MRD fusions aremultifunctional, both small-molecule αv integrin antagonists and thechemically programmed integrin-targeting antibody show remarkableefficacy in preventing the breast cancer metastasis by interfering withαv-mediated cell adhesion and proliferation. MRD fusions containingHERCEPTIN®-2xCon4 (which targets ErbB2 and Ang2) and HERCEPTIN®-Vl14(which targets ErbB2 and VEGF targeting) and HERCEPTIN®-RGD-4C-2xCon4(which targets ErbB2, ang2, and integrin targeting) are effective.

Example 5 VEGF Targeting Antibody-MRD Molecules

An antibody containing an MRD that targets VEGF was constructed. A MRDwhich targets vI 14 (SEQ ID NO:13) was fused at the N-terminus of thekappa chain of 38C2 and HERCEPTIN® using a linker. Expression andtesting of the resulting antibody-MRD fusion constructs demonstratedstrong VEGF binding.

Example 6 IGF1R Targeting Antibody-MRD Molecules

Fusion of an MRD which targets IGF1R (SFYSCLESLVNGPAEKSRG QWDGCRKK (SEQID NO:14)) to the N-terminus of the kappa chain of 38C2 and HERCEPTIN®using the long linker sequence as a connector was studied. Expressionand testing of the resulting antibody-MRD fusion constructs demonstratedstrong IGF1R binding. Additional clones showing high binding to IGR1Rwere identified after several rounds of mutagenesis and screening of theregions described in Table 4. The preferred sequences listed in Table 5bind IGF1R and show no significant or no binding affinity to the insulinreceptor, thereby suggesting specificity for IGF1R.

TABLE 4 Template for further mutagenesis. Name DNA AA Rm2-2-218GTGGAGTGCAGGGCGCCG VECRAP (SEQ ID NO: 50) (SEQ ID NO: 51) Rm2-2-316GCTGAGTGCAGGGCTGGG AECRAG (SEQ ID NO: 52) (SEQ ID NO: 53) Rm2-2-319CAGGAGTGCAGGACGGGG QECRTG (SEQ ID NO: 54) (SEQ ID NO: 55)

TABLE 5 SEQ ID Mutant Amino acid sequence Template  NO Rm4-31NFYQCIEMLASHPAEKSRGQWQECRTGG Rm2-2-319 35 Rm4-33NFYQCIEQLALRPAEKSRGQWQECRTGG Rm2-2-319 36 Rm4-39NFYQCIDLLMAYPAEKSRGQWQECRTGG Rm2-2-319 37 Rm4-310NFYQCIERLVTGPAEKSRGQWQECRTGG Rm2-2-319 38 Rm4-314NFYQCIEYLAMKPAEKSRGQWQECRTGG Rm2-2-319 39 Rm4-316NFYQCIEALQSRPAEKSRGQWQECRTGG Rm2-2-319 40 Rm4-319NFYQCIEALSRSPAEKSRGQWQECRTGG Rm2-2-319 41 Rm4-44NFYQCIEHLSGSPAEKSRGQWQECRTG Rm2-2-319 42 Rm4-45NFYQCIESLAGGPAEKSRGQWQECRTG Rm2-2-319 43 Rm4-46NFYQCIEALVGVPAEKSRGQWQECRTG Rm2-2-319 44 Rm4-49NFYQCIEMLSLPPAEKSRGQWQECRTG Rm2-2-319 45 Rm4-410NFYQCIEVFWGRPAEKSRGQWQECRTG Rm2-2-319 46 Rm4-411NFYQCIEQLSSGPAEKSRGQWQECRTG Rm2-2-319 47 Rm4-415NFYQCIELLSARPAEKSRGQWAECRAG Rm2-2-316 48 Rm4-417NFYQCIEALARTPAEKSRGQWVECRAP Rm2-2-218 49

Example 7 ErbB2 Binding, Ang2-Targeting Antibody-MRD Molecules

An antibody was constructed which contains an MRD that targets Ang2(L17) (SEQ ID NO:7) fused to the light chain of an antibody which bindsto ErbB2. Either the short linker sequence, the long linker sequence, orthe 4th loop in the light chain constant region was used as a linker.FIG. 5 depicts the results of an ELISA using constructs containing anN-terminal fusion of an Ang2 targeting MRD with the ErbB2 antibody withthe short linker peptide (GGGS (SEQ ID NO:1)) (L17-sL-Her), a C-terminalfusion of Ang2 targeting MRD with the ErbB2 antibody with the shortlinker peptide (Her-sL-L17), a C-terminal fusion of Ang2 targeting MRDwith the ErbB2 antibody with the 4th loop in the light chain constantregion (Her-Io-L17), or an N-terminal fusion of Ang2 targeting MRD withthe ErbB2 antibody with the long linker peptide (SSGGGGSGGGGGGSSRSS (SEQID NO:19)) (L17-1L-Her). ErbB2 was bound with varying degrees by all ofthe constructs. However, Ang2 was bound only by Her-sL-L17 andL17-1L-Her.

Example 8 Hepatocyte Growth Factor Receptor Binding, Ang2-TargetingAntibody-MRD Molecules

Fusion of an MRD which targets Ang2 (L17) (SEQ ID NO:7) was made toeither the N-terminus or C-terminus of the light chain of the Metantibody, which binds to hepatocyte growth factor receptor. Either theshort linker sequence or the long linker sequence were used as aconnector. FIG. 6 depicts the results of an ELISA using constructscontaining N-terminal fusion of Ang2 targeting MRD with the Met antibodywith the short linker peptide (GGGS (SEQ ID NO:1)) (L17-sL-Met),N-terminal fusion of Ang2 targeting MRD with the Met antibody with thelong linker peptide (SSGGGGSGGGGGGSSRSS (SEQ ID NO:19)) (L17-1L-Met),and C-terminal fusion of Ang2 targeting MRD with the Met antibody withthe long linker peptide (Met-iL-L17). Expression and testing of theresulting antibody-MRD fusion constructs demonstrated strong Ang2binding when the long linker peptide was used. Fusion of the Ang2targeting MRD to the C-light chain terminus of the antibody resulted inslightly higher binding to Ang2 then fusion of the Ang2 targeting to theN-light chain terminus of the antibody.

Example 9 ErbB2 Binding, Integrin-Targeting Antibody-MRD Molecules

An antibody was constructed which contains an MRD that targets integrinαvβ3 (RGD4C fused to the light chain of an antibody HERCEPTIN® whichbinds to ErbB2 (Her). Either the short linker sequence, the long linkersequence, or the 4th loop in the light chain constant region was used asa linker. FIG. 7 depicts the results of an ELISA using constructscontaining an N-terminal fusion of integrin αvβ3 targeting MRD with theErbB2 antibody with the short linker peptide (GGGS (SEQ ID NO:1))(RGD4C-sL-Her), a C-terminal fusion of integrin αvβ3 targeting MRD withthe ErbB2 antibody with the short linker peptide (Her-sL-RGD4C), aC-terminal fusion of integrin αvβ3 targeting MRD with the ErbB2 antibodywith the 4th loop in the light chain constant region (Her-Io-RGD4C), oran N-terminal fusion of integrin αvβ3 targeting MRD with the ErbB2antibody with the long linker peptide (SSGGGGSGGGGGGSSRSS (SEQ IDNO:19)) (RGD4C-1L-Her). ErbB2 was bound with varying degrees by all ofthe constructs. However, integrin αvβ3 was bound only by RGD4C-1L-Her.

Example 10 Hepatocyte Growth Factor Receptor Binding, Integrin-TargetingAntibody-MRD Molecules

An antibody was constructed which contains an MRD that targets integrinαvβ3 (RGD4C) fused to the light chain of an antibody which binds to thehepatocyte growth factor receptor (Met). Antibody-MRD constructscontaining the long linker sequence were used. FIG. 8 depicts theresults of an ELISA using constructs containing an N-terminal fusion ofintegrin αvβ3 targeting MRD with the hepatocyte growth factor receptorantibody (RGD4C-1L-Met), or a C-terminal fusion of integrin αvβ3targeting MRD with the hepatocyte growth factor receptor antibody(Met-1L-RGD4C). The RGD4C-1L-Met demonstrated strong integrin αvβ3binding.

Example 11 ErbB2 Binding, Insulin-like Growth Factor-IReceptor-Targeting Antibody-MRD Molecules

Antibodies were constructed which contains an MRD that targetsinsulin-like growth factor-I receptor (RP) (SEQ ID NO:14) fused to thelight chain of an antibody which binds to ErbB2 (Her). Either the shortlinker peptide, the long linker peptide, or the 4th loop in the lightchain constant region was used as a linker (Carter et al., Proc NatlAcad Sci 89:4285-9 (1992); U.S. Pat. No. 5,677,171; and ATCC Deposit10463, each of which is herein incorporated by reference). FIG. 9depicts the results of an ELISA using constructs containing anN-terminal fusion of insulin-like growth factor-I receptor targeting MRDwith the ErbB2 antibody with the short linker peptide (RP-sL-Her), aC-terminal fusion of insulin-like growth factor-I receptor targeting MRDwith the ErbB2 antibody and the short linker peptide (Her-sL-RP), aC-terminal fusion of insulin-like growth factor-I receptor targeting MRDwith the ErbB2 antibody with the 4th loop in the light chain constantregion (Her-Io-RP), an N-terminal fusion of insulin-like growth factor-Ireceptor targeting MRD with the ErbB2 antibody with the long linkerpeptide (RP-IL-Her), or a C-terminal fusion of insulin-like growthfactor-I receptor targeting MRD with the ErbB2 antibody with the longlinker peptide (Her-IL-RP). ErbB2 was bound with varying degrees by allof the constructs. Insulin-like growth factor-I receptor was bound byRP-IL-Her.

Example 12 ErbB2 Binding. VEGF-Targeting Antibody-MRD Molecules

Fusion of an MRD which targets VEGF (VI 14) (SEQ ID NO:13) (FairbrotherW. J., et al, Biochemistry. 37:177754-64 (1998)) was made to theN-terminus of the light chain of a ErbB2-binding antibody (Her). Amedium linker peptide (SSGGGGSGGGGGGSS (SEQ ID NO:2)) was used as aconnector. FIG. 10 depicts the results of an ELISA using a constructcontaining an N-terminal fusion of VEGF targeting MRD with theErbB2-binding antibody with the medium linker peptide (VI 14-mL-Her).Expression and testing of the resulting antibody-MRD fusion constructdemonstrated strong VEGF and ErbB2 binding.

Example 13 Integrin Targeting Antibody-MRD Molecules

Fusion of an MRD which targets integrin αvβ3 (RGD) to the N-terminus ofthe light chain of 38C2 using the medium linker peptide as a connectorwas studied. FIG. 11 demonstrates that expression and testing of theresulting antibody-MRD fusion construct had strong integrin αvβ3binding.

Example 14 Ang2 Targeting Antibody-MRD Molecules

Fusion of an MRD which targets Ang2 (L 17) (SEQ ID NO:7) to theC-terminus of the light chain of 38C2 using the short linker sequence asa connector was studied. FIG. 12 demonstrates that expression andtesting of the resulting antibody-MRD fusion construct had strong Ang2binding.

Example 15 ErbB2 Binding, Integrin and Ang2 Targeting Antibody-MRDMolecules

An MRD which targets integrin αvβ3 (RGD4C) was connected to theN-terminus of the light chain of an ErbB2 targeting antibody (Her) witha medium linker, and an Ang2 (L17) targeting MRD was connected by ashort linker to the C-terminus of the same ErbB2 targeting antibody(RGD4C-mL-Her-sL-L17). FIG. 13 demonstrates that the resultingantibody-MRD fusion construct bound to integrin, Ang2, and ErbB2.

Example 16 ErbB2 Binding, Integrin-Targeting Antibody-MRD Molecules

An antibody was constructed which contains an MRD that targets integrinαvβ3 (RGD4C) fused to the N-terminus of the heavy chain of an antibodywhich binds to ErbB2 (Her) using the medium linker as a connector(RGD4C-mL-her-heavy). FIG. 14 depicts the results of an ELISA using theconstruct. Both integrin and ErbB2 were bound by the construct.

Example 17 ErbB2 or Hepatocyte Growth Factor Receptor Binding, andIntegrin, Ang2 or Insulin-Like Growth Factor-I Receptor-TargetingAntibody-MRD Molecules with the Short Linker Peptide

Antibody-MRD molecules were constructed which contain ErbB2 orhepatocyte growth factor receptor binding antibodies, and integrin αvβ3,Ang2 or insulin-like growth factor-I receptor-targeting MRD regions werelinked with the short linker peptide to the light chain of the antibody.FIG. 15 depicts the results of an ELISA using constructs containing anN-terminal fusion of Ang2 targeting MRD fused to the ErbB2 antibody(L17-sL-Her), an N-terminal fusion of integrin-targeting MRD with theErbB2 antibody (RGD4C-sL-Her), an N-terminal fusion of insulin-likegrowth factor-I receptor targeting MRD with the ErbB2 binding antibody(RP-sL-Her), a C-terminal fusion of Ang2 targeting MRD with thehepatocyte growth factor receptor binding antibody (L17-sL-Met), aC-terminal fusion of Ang2 targeting MRD with the ErbB2 binding antibody(Her-sL-L17), a C-terminal fusion of integrin targeting MRD with theErbB2 binding antibody (Her-sL-RGD4C), or a C-terminal fusion ofinsulin-like growth factor-I receptor targeting MRD with the ErbB2binding antibody (Her-sL-RP). ErbB2 was bound with varying degrees bythe antibody-MRD constructs, with the exception of the constructcontaining the hepatocyte growth factor receptor-binding antibody.Antigen was bound only by the Her-sL-L17 construct.

Example 18 ErbB2 or Hepatocyte Growth Factor Receptor Binding, andIntegrin, Ang2 or Insulin-Like Growth Factor-I Receptor-TargetingAntibody-MRD Molecules with the Long Linker Peptide

Antibody-MRD molecules were constructed which contain ErbB2 orhepatocyte growth factor receptor binding antibodies, and integrin αvβ3,Ang2 or insulin-like growth factor-I receptor-targeting MRD regionslinked with the long linker peptide to the light chain of the antibody.FIG. 16 depicts the results of an ELISA using constructs containing anN-terminal fusion of Ang2 targeting MRD fused to the ErbB2 antibody(L17-1L-Her), an N-terminal fusion of integrin-targeting MRD with theErbB2 antibody (RGD4C-1L-Her), an N-terminal fusion of insulin-likegrowth factor-I receptor-targeting MRD with the ErbB2 binding antibody(RP-IL-Her), a C-terminal fusion of Ang2 targeting MRD with thehepatocyte growth factor receptor binding antibody (L17-1L-Met), aC-terminal fusion of integrin targeting MRD with the hepatocyte growthfactor receptor binding antibody (RGD4C-1L-Met), a C-terminal fusion ofAng2 targeting MRD with the insulin-like growth factor-I receptorbinding antibody (Her-IL-RP), a C-terminal fusion of Ang2 targeting MRDwith the hepatocyte growth factor receptor binding antibody(Met-1L-L17), or a C-terminal fusion of integrin targeting MRD with thehepatocyte growth factor receptor binding antibody (Met-1L-RGD4C). Asshown in FIG. 16, antibody-MRD fusions are effective to bind antigen andErbB2. Lu et al. J Biol Chem. 2005 May 20; 280(20): 19665-72. Epub 2005Mar. 9; Lu et al. J Biol Chem. 2004 Jan. 23; 279(4):2856-65. Epub 2003Oct. 23.

Example 19 Expression and Purification of Antibodies Containing MRDs

Molecular recognition domains were constructed and expressed in a pcDNA3.3 vector as fusion proteins with either the heavy or light chains ofantibodies. For protein production, plasmid DNAs encoding the heavy andlight chains of the antibodies containing MRDs were first transformedinto chemically competent bacteria in order to produce large amounts ofDNA for transient transfection. Single transformants were propagated inLB media and purified using Qiagen's Endotoxin Free Plasmid Kits.Briefly, cells from an overnight culture were lysed; lysates wereclarified and applied to an anion-exchange column, and then subjected toa wash step and eluted with high salt. Plasmids were precipitated,washed, and resuspended in sterile water.

HEK293T cells were expanded to the desired final batch size (about 5 L)prior to transfection. The purified plasmid (1 mg per liter ofproduction) was complexed with the polyethylenimine (PEI) transfectionreagent, added to the shake flask culture, and incubated at 37° C. Theculture was monitored daily for cell count, cell diameter, andviability. The conditioned medium was harvested and stored at −80° C.until purification.

Antibodies containing MRDs were purified from the conditioned mediumusing affinity chromatography. Culture supernatant was filter clarifiedand applied directly to a chromatography column containing recombinantProtein A Sepharose (GE Healthcare). The column was washed, and boundantibodies containing MRDs were eluted by lowering buffer pH. Followingelution, eluate fractions were immediately adjusted to physiologic pH.Following Protein A affinity purification, an additional optionalpolishing chromatographic step can be performed as needed.

Purified proteins were dialyzed into PBS, concentrated to ˜1-4 mg/ml,sterile filtered, aliquoted aseptically, and stored frozen at −80° C.All steps of the purification were monitored by SDS-PAGE-Coomassie, andprecautions were taken during the purification to keep endotoxin levelsas minimal as possible.

The final product was analyzed for endotoxin levels (EndoSafe), purity(SDS-PAGE-coomassie, analytical SEC-HPLC), protein identity (Westernblot), and yield (Bradford assay). An additional size exclusion HPLCanalysis was performed to assess the level of aggregates.

The data presented in Table 6 indicate that the antibodies containingMRDs can be expressed and purified using conventional techniques.

TABLE 6 Zybody Yield (mg) Purity Aggregates (%) Endotoxin (EU/ml)HER2xCon4(H) 36 >90% 4.6 <1 HER-Im32(H) 57 >90% 1 2.02 HER-Im32(L)98 >90% 2 3.26 AVA-Im32(H) 12 >90% 0 <1

Example 20 Simultaneous Binding of HER Lm32(H) and HER Lm32 (1) to Her2and Ang2 A. Methods

Ninety-six-well plates were coated overnight with rHER2-Fc (R&Dcat#1129-ER-050) at 20 ng/ml (100 μl/well). Wells are blocked for 3.25hours with 250 μl Blocking buffer (Thermo Cat# N502), followed by 4washes with 300 μl wash buffer (PBS, 0.1% tween). Antibodies containingMRDs (HER-Im32(H), HER-Im32(L), and AVA-Im32(H)) and antibodies(HERCEPTIN®) were serially diluted in Blocking buffer, containing 1.94μg/ml biotinylated Ang2 (R&D cat#BT633) and added to wells for 2 hoursat RT. After washing (8×300 μl wash buffer), parallel samples receivedeither HRP-conjugated anti-human kappa chain mAb-(Abcam, cat #ab79115-1)diluted 1:1000 in Blocking buffer or HRP-conjugated streptavidin (ThermoScientific cat#N100) diluted 1:4000 diluted in Blocking buffer. Afterincubation for 1 hour at RT, wells were washed (8×300 μl wash buffer)prior to receiving 100 μl of TMB substrate (KPL Laboratories). Colordevelopment was stopped with 100 μl of H₂SO₄, and absorbance was read at450 nm.

B. Results

As detected with anti-human kappa chain mAb, both a HERCEPTIN®-basedantibody or HERCEPTIN®-based antibodies containing MRDs bind to Her2 Fcin the presence of Ang2 in a dose dependent manner (FIG. 18A). Only theHERCEPTIN®-based antibodies containing MRDs (HER-Im32(H) andHER-Im32(L)) exhibit simultaneous binding to Her2 Fc and Ang2, asdetected by HRP-conjugated streptavidin (FIG. 18B).

Example 21 Simultaneous Binding of HER-Im32 (H) and HER-Im32 (L) to HER2and Angiopoietin-2

The ability of HER-Im32 (H) and HER-Im32 (L) simultaneously bind to Her2expressed on the surface of breast carcinoma cells BT-474, and to Ang2in solution, was determined by flow cytometry. Mouse anti-human Ig-FITCwas used for detection of the heavy chain of the antibodies containingMRDs, and Ang2-biotin/streptavidin-PE was used for detection of the Im32MRD. Cells that bind Her2 and Ang2 simultaneously are expected to bedetected as double positive for FITC and PE fluorescence.

One million HER2 positive breast carcinoma cells BT-474 were incubatedwith 1 μg HER-Im32(H) or HER-Im32(L) for 25 minutes at RT. Afterwashing, cells were incubated with 200 ng/mL Ang2 biotin (R&D systems)for 25 minutes at RT and then with 20 μL of mouse anti-human Ig-FITC andStreptavidin-PE for 15 minutes. After washing with 2 mL buffer, cellswere analyzed by flow cytometry (FACS Canto II, BD).

In order to confirm the specificity of binding of HER-Im32(H) andHER-Im32(L) to HER2 on BT-474 cells, binding was determined in thepresence of 10-fold excess of HERCEPTIN®. In these experiments,antibodies containing MRDs (1 μg) were incubated with one million BT-474cells in the absence or presence of 10 μg HERCEPTIN® for 25 minutes atRT. Binding of antibodies containing MRDs to HER2 was determined byincubating with 200 ng/mL Ang2 biotin followed by detection withstreptavidin-PE.

The data presented in FIG. 18A demonstrate that both HER-Im32(H) andHER-Im32(L), bind simultaneously to HER2 and Ang2. In both cases, thecells exhibited bright dual fluorescence in the FITC and PE fluorescencechannels. The fact that HER-Im32(H) and HER-Im32(L) binding to HER2 iscompletely inhibited by HERCEPTIN® (FIG. 18B) indicates that the bindingis specific.

Example 22 Antibody-MRDs Containing Heavy Chain Fusions Bind to Targets

To assess the ability of Im32-containing antiboides to block theinteraction of Ang2 with its receptor Tie2, their effect on the bindingof soluble Tie2 to plate-bound Ang2 was determined by ELISA.

Ang2 (R&D Systems, catalog#623-AN) was coated on a 96-well plate (ThermoElectron, cat#3855) at 200 ng/mL in PBS overnight at 4° C. The plate wasthen incubated with 100 μL of blocking solution (Thermo Scientific,cat#N502) for 1 hour at RT. After washing the plate 4 times with 0.1%Tween-20 in PBS, the plate bound Ang2 was incubated with 0.5 μg/mLsoluble Tie2 (R&D Systems, cat#313-TI) in the absence or presence ofvarious concentrations of serially diluted antibodies containing MRDsfor 1 hour at RT. After washing 4 times, 100 μL of 0.5 μg/mL anti Tie2antibody (cat#BAM3313, R&D Systems) was added and incubated at RT for 1hour. Tie2 binding to Ang2 was detected by incubation with 1:1000diluted goat anti-mouse-HRP (BD Pharmingen, cat#554002) for 1 hour atRT. The plate was washed 4 times and incubated with 100 μL TMB reagentfor 10 minutes at RT. After stopping the reaction with 100 μL of 0.36NH₂SO₄, the plate was read at 450 nm using a spectrophotometer.

As presented in FIG. 19A, HER-Im32(H), and HER-Im32(L) inhibited Tie2binding to plate-bound Ang2 in a dose-dependent fashion. All testedIm32-containing antibodies demonstrated comparable inhibitory effectswith IC-50 values of 4 nM for HER-Im32 (H), and 8 nM for HER-Im32(L).

Example 23 Binding of HER-Im32(H) and HER-Im32(L) to HER2 Expressed onBreast Cancer Cells

To determine the relative binding affinity of HERCEPTIN®-basedantibodies containing MRDs to cell surface HER2 compared to HERCEPTIN®,a competitive binding assay was performed with Eu-labeled HERCEPTIN®.

HERCEPTIN® was labeled with Eu3+ using a dissociation-enhancedlanthanide fluorescence immunoassay (DELFIA) Europium-labeling kit(Perkin Elmer Life Sciences, cat#1244-302) following the manufacturer'sinstructions. The labeling agent is the Eu-chelate ofN1-(p-isothiocynateobenzyl) diethylenetriamine N1, N2, N3,N3-tetraacetic acid (DTTA). The DTTA group forms a stable complex withEu3+, and the isothiocynate group reacts with amino groups on theprotein at alkaline pH to form a stable, covalent thio-urea bond.HERCEPTIN® (0.2 mg in 200 mL sodium bicarbonate buffer pH 9.3) waslabeled with 0.2 mg of labeling agent at 4° C. overnight. Eu-labeledHERCEPTIN® was purified by spin column using 50 mmol/L tris-HCl pH 7.5and 0.9% NaCl elution buffer.

The Eu-HERCEPTIN® binding assay was performed by incubating 0.5-1million BT-474 or SK-BR3 breast cancer cells per well in a 96-well platewith 2-5 nM Eu-HERCEPTIN® in the presence of various concentrations ofunlabeled HERCEPTIN®-based antibodies containing MRDs or HERCEPTIN® for1 hour at RT. Unbound Eu-HERCEPTIN® was removed by washing using 200 μLcomplete medium. Cells were then resuspended in 100 μL complete mediumand 80 μL of cell suspension transferred to a 96-well isoplate. Cellswere incubated with 100 μL Delfia enhancer solution at RT for 10 minutesand cell bound Eu-HERCEPTIN® was detected by Envison (Perkin Elmer).

The inhibition of binding curves obtained using BT-474 cells arepresented in FIG. 21. Eu-HERCEPTIN® binding to BT-474 was inhibited byHERCEPTIN® and HERCEPTIN®-based antibodies containing MRDs in adose-dependent fashion. Comparable IC-50 values were observed: 4.7 nMfor HER-Im32(H), 5.7 nM for HER-Im32(L), and 3.7 nM for unlabeledHERCEPTIN®.

Example 24 Inhibition of Breast Cancer Cells Proliferation byHERCEPTIN®-Based Antibodies Containing MRDs

HERCEPTIN sensitive breast cancer cells SK-BR-3 expressing HER2neoreceptor were also tested in a bioassay. SK-BR-3 cells (2000 cell/well)were plated in 96 well plates (Costar) in complete McCoy's growth mediumcontaining 2 mM glutamine, pen/strep (Invitrogen) and 10% FBS (HyClone).The cells were cultured for 24 hours at 37° C., 5% CO₂, 85% humidity. Onthe following day, the growth medium was replaced with starvation medium(McCoy's medium containing 2 mM glutamine, pen/strep, 0.5% FBS). Nineserial dilutions (concentration range 5000-7.8 ng/ml) of HERCEPTIN® andHERCEPTIN®-based antibodies containing MRDs were prepared in completegrowth medium. After 24 hours of incubation, the starvation medium wasremoved, and the serial dilutions of HERCEPTIN® and HERCEPTIN®-basedantibodies containing MRDs were transferred to the plates intriplicates. The cells were cultured for 6 days. The proliferation wasquantified using the CellTiter Glo luminescence method.

The IC50 values determined using a four-parameter logistic model were asfollows: 0.49+/−0.17 nm for HER-Im32(H), 0.81+/−0.19 nm for HER-Im32(L),and 0.67+/−0.15 nm for HER-con4(H). All tested HERCEPTIN®-basedantibodies containing MRDs were able to inhibit the proliferation of theSK-BR-3 breast carcinoma cells with subnanomolar IC-50 values. Therepresentative fitted dose response curves shown in FIGS. 22A-Cdemonstrate that HERCEPTIN®-based antibodies containing MRDs inhibitcell proliferation with similar potency to HERCEPTIN®.

Example 25 Antibody Dependent Cytotoxicity of HERCEPTIN®-BasedAntibodies Containing MRDs

To assess the ability of antibodies containing MRDs to mediate ADCC invitro, a cytotoxicity assay based on the “DELFIA EUTDA Cytotoxicityreagents AD0116” kit (PerkinElmer) was used. In this assay, the targetcells were labeled with a hydrophobic fluorescence enhancing ligand(BADTA, bis(acetoxymethyl) 2,2′:6′,2″-terpyridine-6,6″-dicarboxylate).Upon entering the cells, BADTA is converted to a hydrophilic compound(TDA, 2,2′:6′,2″-terpyridine-6,6″-dicarboxylic acid) by cytoplasmicesterases mediated cleavage and no longer can cross the membrane. Aftercell lysis, TDA is released into a medium containing Eu3+ solution toform a fluorescent chelate (EuTDA). The fluorescence intensity isdirectly proportional to the number of lysed cells.

HERCEPTIN® and HERCEPTIN®-based antibodies containing MRDs can mediateADCC on Her2 positive breast cancer cells by binding to the HER2receptor on the surface of the target cells and activating the effectorcells present in human PBMCs by interacting with their FcγRIIIreceptors. A HER2 positive human breast cancer cell line SK-BR-3 wasused as a target cell line in the ADCC assay to demonstrate this.

SK-BR-3 cells were detached with 0.05% trypsin-versene and resuspendedat 1×10⁶ cells/mL in RPMI1640 medium containing 2 mM glutamine,pen/strep and 10% FBS (complete growth medium). 2×10⁶ cells in 2 mL ofmedia were transferred into 15 mL tube and 10 μl of BADTA reagent wasadded. The cell suspension was mixed gently and placed in the incubatorat 37° C., 5% CO₂ and 85% humidity for 15 minutes. Seven 10× serialdilutions starting with 5 μg/mL of HERCEPTIN® or HERCEPTIN®-basedantibodies containing MRDs were prepared during cell labeling.

After incubation with BADTA, cells were washed 4 times in completegrowth medium containing 2.5 mM Probenecid. Between washes, cells werespun down by centrifugation at 1000 rpm for 3 minutes. After the lastwash, labeled SK-BR-3 cells were resuspended in 10 mL complete growthmedium and 50 μl of cells were added to each well of 96 well plate,except background wells. 50 μl of serial dilutions of HERCEPTIN® orHERCEPTIN®-based antibodies containing MRDs were added to the designatedwells. The plates were transferred to the incubator at 37° C., 5% CO₂and 85% humidity for 30 minutes.

PBMCs that were purified from human peripheral blood one day prior theADCC assay, were washed once in RPMI1640 with 2 mM glutamine, pen/strep,10% FBS. 10 mL of the PBMCs suspension with 2.5×10⁶ cells/mL wasprepared. 100 μl of PBMC suspension was transferred into wellscontaining target cells and HERCEPTIN® or HERCEPTIN®-based antibodiescontaining MRDs in triplicate. The following controls were placed indesignated wells: Spontaneous release (target cells without effectorcells), Maximum release (lysed target cells) and Background (mediawithout cells). The plates were incubated for 2.5 hours an incubatorwith 37° C., 5% CO₂ and 85% humidity.

After incubation 20 μl of the supernatant was transferred to anotherplate and 200 μl of Europium solution was added. The plates wereincubated on a plate shaker at RT for 15 minutes. The time resolvedfluorescence was measured using PerkinElmer EnVision 2104 MultilabelReader.

The following formula was used to calculate percentage of Specificrelease:

$\frac{{{Experimental}\mspace{14mu} {release}\mspace{14mu} ({counts})} - {{Spontaneous}\mspace{14mu} {release}\mspace{14mu} ({counts})}}{{{Maximum}\mspace{14mu} {release}\mspace{14mu} ({counts})} - {{Spontaneous}\mspace{14mu} {release}\mspace{14mu} ({counts})}} \times 100$

The IC50 values calculated by a four-parameter logistic model were asfollows: 0.213+/−0.077 nM for HER-Im32(H), 0.204+/−0.036 nM forHER-Im32(L), and 0.067+/−0.015 nM for HER-con4(H). All tested antibodiescontaining MRDs demonstrated robust ADCC activity with subnanomolarIC-50 values. The representative fitted dose response curves shown inFIGS. 23A and 23B demonstrate that antibodies containing MRDs are ableto mediate cell dependent cytotoxicity with comparable potency toHERCEPTIN®.

Example 26 MRD-Containing Antibodies Inhibit Tumor Proliferation In Vivo

In order to determine the effectiveness of MRD-containing antibodies invivo, their efficacy in a mouse Colo5 tumor model was assessed. In theseexperiments, tumors were implanted into the right flank of six-week oldfemal athymic nude mice by injecting 5×10⁶ Colo205 cells suspended in100 μL PBS. Three groups of eight animals each received intraperitonealinjections of 5 mg/kg of antibody (Herceptin) or an MRD-containingantibody (HER-2xCon4; “H2xCon4”) in 100 μL PBS every third day startingat day 6 after tumor implantation. The results, shown in FIG. 24,demonstrate that the MRD-containing antibody was more efficient atinhibiting tumor growth than Herceptin®.

Example 27 In Vivo Assays to Evaluate MRD-Containing Antibodies

In order to determine the efficacy of MRD-containing antibodies in vivo,animal models are treated with an antibody and an MRD-containingantibody and the results are compared.

MRD-containing anti-HER2 antibodies are tested in the following in vivomodel. NIH 3T3 cells transfected with a HER2 expression plasmid areinjected into nu/nu athymic mice subcutaneously at a dose of 10⁶ cellsin 0.1 ml of phophate-buffered saline as described in U.S. Pat. No.6,399,063, which is herein incorporated by reference in its entirety. Ondays, 0, 1, 5, and every 4 days thereafter 100 μg of a HER2 antibody, anang2-containing HER2 antibody, an igf1r-containing HER2 antibody and anang2-igf1r-containing HER2 antibody are injected intraperitoneally.Tumor occurrence and size are monitored for one month. Increases inefficacy of MRD-containing antibodies compared to antibodies areobserved.

MRD-containing anti-VEGF antibodies are tested in the following in vivomodel. RIP-TβAg mice are provided with high-sugar chow and 5% sugarwater as described in U.S. Published Application No. 2008/0248033, whichis herein incorporated by reference in its entirety. At 9-9.5 or 11-12weeks of age, the mice are treated twice-weekly with intra-peritonealinjections of mg/kg of an anti-VEGF antibody, ang2-containing VEGFantibody, ifg1r-containing VEGF antibody or ang2- and igf1r-containingantibody. The 9-9.5 week mice are treating for 14 days and thenexamined. The 11-12 week mice are examined after 7, 14, and 21 days oftreatment. The pancrease and speen of the mice are removed and analzyed.Tumor number is determined by dissecting out each sperical tumor andcounting. Tumor burden is determined by calculating the sum of thevolume of all tumors within the pancreas of a mouse. The effect onangigogenesis is determined by calculating the mean number of angiogenicislets observed. Increases in efficacy of MRD-containing antibodiescompared to antibodies are observed.

Although the invention has been described with reference to the aboveexamples, it will be understood that modifications and variations areencompassed within the spirit and scope of the invention. Accordingly,the invention is limited only by the following claims

All publications, patents, patent applications, internet sites, andaccession numbers/database sequences (including both polynucleotide andpolypeptide sequences) cited are herein incorporated by reference intheir entirety for all purposes to the same extent as if each individualpublication, patent, patent application, internet site, or accessionnumber/database sequence were specifically and individually indicated tobe so incorporated by reference.

What is claimed is:
 1. A complex comprising an antibody and at least onemodular recognition domain (MRD), wherein the antibody is (a) murine,(b) chimeric, (c) humanized, or (d) human.
 2. The complex of claim 1,wherein the antibody is multispecific.
 3. The complex of claim 1,wherein the antibody is an IgG.
 4. The complex of claim 1, wherein theMRD binds to a target selected from the group consisting of: anintegrin, a cytokine, an angiogenic cytokine, vascular endothelialgrowth factor (VEGF), insulin-like growth factor-I receptor (IGF-IR), atumor antigen, CD20, an epidermal growth factor receptor (EGFR), theErbB2 receptor, the ErbB3 receptor, tumor associated surface antigenepithelial cell adhesion molecule (Ep-CAM), an angiogenic factor, anangiogenic receptor, cell surface antigen, soluble ligand, vascularhoming peptide, and nerve growth factor.
 5. The complex of claim 4,wherein the target is a human protein.
 6. The complex of claim 1,wherein the antibody binds to a target selected from the groupconsisting of an integrin, a cyokine, an angiogenic cytokine, vascularendothelial growth factor (VEGF), insulin-like growth factor-I receptor(IGF-IR), a tumor antigen, CD20, an epidermal growth factor receptor(EGFR), the ErbB2 receptor, the ErbB3 receptor, tumor associated surfaceantigen epithelial cell adhesion molecule (Ep-CAM), an angiogenicfactor, an angiogenic receptor, cell surface antigen, soluble ligand,vascular homing peptide, and nerve growth factor.
 7. The complex ofclaim 1, wherein the antibody is selected from the group consisting oftrastuzumab, cetuximab, and panitumumab.
 8. The complex of claim 1,wherein the antibody and the MRD bind to the same molecule.
 9. Thecomplex of claim 1, wherein the antibody and the MRD bind to differentmolecules.
 10. The complex of claim 1, wherein an MRD is located on aterminus selected from the group consisting of (a) the N-terminus of theantibody heavy chain, (b) the N-terminus of the antibody light chain,(c) the C-terminus of the antibody heavy chain, and (d) the C-terminusof the antibody light chain.
 11. The complex of claim 10, wherein afirst MRD is located on (c) the C-terminus of the antibody heavy chainand a second MRD is located on (d) the C-terminus of the antibody lightchain.
 12. The complex of claim 1, wherein the antibody and the MRD areoperably linked through a linker peptide.
 13. The complex of claim 12,wherein the linker comprises a sequence selected from the groupconsisting of: SEQ ID NO:1, SEQ ID NO:2, and SEQ ID NO:19.
 14. Thecomplex of claim 1, wherein the antibody is capable of binding to anantibody target and an MRD target simultaneously.
 15. The complex ofclaim 1, wherein the antibody comprises at least two MRDs.
 16. Thecomplex of claim 15, wherein two MRDs are homo-multimeric.
 17. Thecomplex of claim 15, wherein two MRDs are hetero-multimeric.
 18. Thecomplex of claim 17, wherein the hetero-multimeric MRDs bind to the sametarget.
 19. The complex of claim 17, wherein the hetero-multimeric MRDsbind to different targets.
 20. The complex of claim 15, wherein the twoMRDs are located on the same antibody terminus or on different antibodytermini.